: permanent and operational. A constant is characterized by the fact that all data is recorded on a storage medium - a hard disk. After turning off the computer, all data stored on the hard drive remains safe and sound. Otherwise, the situation is with operational memory yu - information is stored in it only while the computer is running. Why is operational memory? First of all, this type of memory is very fast, accessing it takes the operating system much less time than accessing a hard disk. In addition, running programs are stored in RAM. Open the Task Manager (Ctrl+Alt+Del) and look at the "Memory" section - you will see the amount of RAM used by currently running programs. As programs run, the amount of memory they use can change. The more RAM your computer has, the more productive it will be. True, the 32-bit version of the Windows XP operating system does not support more than three gigabytes of memory. Its 64-bit version supports up to 128 gigabytes of RAM, in reality, in this case, everything depends on the capabilities of the motherboard. The Windows 7 operating system in the 32-bit version supports 4 gigabytes of RAM. In its 64-bit version, the size of the supported RAM depends on the OS version: in the initial ones - Home Basic and Home Premium - it is 8 and 16 gigabytes, respectively, the Professional, Enterprise and Ultimate versions support up to 192 gigabytes. Of course, here, too, the actual amount of memory supported will largely depend on the capabilities of the motherboard. The type of RAM also matters: SIMM, DIMM, DDR, DDR2, DDR3. The first two are already very outdated, so it is quite difficult to meet them. The remaining three types are installed on most modern computers. The more modern the used memory the faster it works. Memory chips are assembled into modules, they are also called slats. The modules are installed in their designated slots on the motherboard.
RAM is one type of volatile memory. RAM is used in many modern devices, from a personal computer to communicators.
The RAM of a computer stores the information necessary for the operation of the central processor. This device receives all the necessary data from the RAM boards. During the operation of RAM, the principle of addressability is used, i.e. each piece of information has an individual address.
The overall performance of a personal computer depends on the amount of RAM. This is not surprising, because the more information can be simultaneously stored in RAM, the more tasks can be quickly performed by the central processor. If the CPU received information from the hard drive, then modern computers would run much slower. On computers with a large amount of RAM, you can use many different programs at the same time without compromising their performance.
Data transfer between the central processor and RAM boards occurs through special buses. They have a high transfer rate, which provides almost instantaneous exchange of the necessary data.
There are two main types of RAM: static and dynamic. Memory of the second type is used in RAM boards. Static memory processes and returns information much faster, but its production is much more expensive. That is why static-type memory is used to create central processing units and video card chips. It should be noted that the use of ultra-fast RAM (cache) increases the overall performance of the computer several times. This is due to the fact that data is transferred to this area from conventional memory cards in advance.
For dynamic memory to work, it is necessary to constantly replenish the charge of the capacitors used in the creation of RAM boards. This leads to the fact that for certain periods of time the boards cannot perform their tasks.
Gone are the days when a computer was considered only a toy for especially wealthy people. Today it is a common working tool that almost every person encounters at home or at work every day.
Unfortunately, not everyone has at least an initial level of computer literacy. This is especially evident at the moment when a PC upgrade is required. Often people do not even know what RAM is, although in many cases it is its replacement (or increase in volume) that can give an old computer noticeably more "agility". Therefore, in this article we will describe what this component is responsible for, how to choose it, and also touch on some other nuances.
Basic concepts
So In the literature, it is abbreviated as RAM (random access memory), the English version is even more common - RAM. This component is necessary for temporary data storage, which ensures the normal functioning of the software. Usually, its microcircuits are connected to the motherboard through the appropriate connectors, but often they are simply soldered on it.
In general, the main task of RAM is to be a buffer between the processor and the hard drive while the computer is running, storing all the “intermediate” data and contributing to the high speed of the system (Intel RAM is especially good in this regard).
Important note
Often, beginners do not distinguish at all between RAM and permanent memory (that is, a hard drive). It must be clearly understood that RAM is volatile, all data from its microcircuits is deleted at the moment the computer is turned off. It should be noted that this does not happen with hard drives. To some extent, flash drives are a separate subspecies, since they do not require energy at all to store recorded information.
Structure
We figured out what RAM is. But how is it organized and what is it characterized by? In fact, the structure of the RAM is similar to a set of honeycombs. Each cell stores some amount of data (1-4 bits). Note that each "cell" has its own personal address. It is subdivided into data on the location of the horizontal building (Row) and vertical position (Column).
Simply put, each cell is a capacitor, which is able to store an electrical discharge for a certain time. Thanks to special algorithms, the data recorded in this way is converted into a format understandable to the computer. In addition, to transmit the address of the row and / or vertical column of the cell, a signal of the RAS and CAS types, respectively, is used. However, all this refers to such matters that the average user does not need to know about.
How does it all work?
If you read carefully, you already understood that the necessary information is first downloaded from the hard disk, “stored” in RAM modules, and then processed by the central processor. All these devices can exchange data directly, but much more often all this happens with the participation of cache memory.
It is available for both processors and hard drives. Cache memory is designed to store especially frequently used information. Its presence can significantly speed up the performance of the entire system as a whole, since the speed of the hard disk and RAM is much lower than that of the central processor itself. If the volume of this drive is sufficient, it is possible to completely get rid of forced downtime and inactivity of the equipment.
The RAM itself is controlled by a separate controller, which is located on the north bridge of the motherboard. In addition, it also depends on the connection of the central processor to other devices that use "fat" buses for data transfer (all the same RAM, graphics subsystem).
Should know
When the RAM is working and information is being written to some cell, then all the data that was there before will be lost forever. It should be noted that modern operating systems support the breakdown of RAM into several sections at once, this provides a noticeably increased speed. How does it all work?
The fact is that modern RAM devices are large, and therefore they can accommodate data from several processes running simultaneously. Of course, the CPU is also capable of handling several hundred tasks at a time. To ensure the normal operation of the computer, a system of dynamic memory allocation was developed. In this case, for each task that is currently “under consideration” by the central processor, its own, dynamically changing block of RAM is assigned.
Why such difficulties?
Such a division helps to manage the available amount of RAM much more economically, since more space is allocated to the most important and priority tasks. It should be noted that really high-quality dynamic allocation is available only to users of the latest versions of operating systems.
In addition, the old distribution methods that were used in the days of Windows 98 or earlier systems make the programs of those years completely inoperative on modern versions of the OS. Even if you have 4 gigabytes of RAM "on board", the new generation RAM simply will not understand the old instructions.
Possible operating modes
Note that RAM can operate in the following modes:
- Single channel. Single channel, asymmetric mode. It turns on in two cases: when there is only one memory chip in the system, or if the user has installed several chips from different manufacturers that differ from each other in their parameters. It is important to note that the system in the second case will focus on the weakest RAM module, operating at its frequency.
- dual mode. Dual channel, symmetrical mode. To do this, absolutely identical rams of RAM are installed in two slots, as a result of which the data transfer rate can increase significantly. Accordingly, to activate this mode, chips must be placed in slots 1 and 3 and / or 2 and 4 slots. Please note that 2nd generation RAM (DDR2) can only work in this mode (most often).
- Triple mode. Three-channel mode is quite rare lately. In general, it is a variation of the previous mode, but it is used only on those motherboards that have three slots for installing RAM modules. It should be noted that in practice this mode is very often inferior to the dual-channel option (any RAM test will indicate this).
- Flex Mode (flexible). This is a very interesting mode that allows you to "squeeze" the maximum performance from two different memory sticks (it is important that they be the same in frequency). The modules are installed in the same order as the two-channel version.
What happens after turning on the computer?
As we have already said, the exchange of information between the most important devices of a computer takes place using cache memory. It, in turn, is controlled by a special controller and a program for RAM. What are they needed for? The fact is that it is these components that determine the priority of tasks, choosing those programs whose information needs to be written to the cache, as well as applications that can “get by” with ordinary RAM.
When the computer is turned on, all the necessary data, elements of the operating system itself and programs that should start automatically immediately after the computer starts, are immediately written to the RAM from the hard disk. Of course, before this, a quick test of RAM is carried out (to identify the most serious malfunctions). After that, the data is processed by the central processor. The scheme repeats cyclically, all the time until you turn off the computer.
Everything is fine, but what happens if the amount of RAM installed in the system is no longer enough for the software and the system to work?
What if there aren't enough volumes?
That's when the paging file comes into play, with which all users of not very powerful, outdated machines are probably familiar. This file is located on the system hard drive, and all data is written there that the RAM simply does not fit, the price of which is quite high (from one and a half thousand for 2 GB), so many people face this problem.
You yourself can understand that due to the low speed of the hard drive in this case, the performance of the entire operating system suffers greatly. In addition, due to constant access to the hard drive, the latter wears out physically much faster.
On the contrary, when you have a lot of RAM, you can greatly benefit in performance. To do this, you need a special program for RAM, which will create a virtual hard disk directly in it. You can transfer all applications that require increased performance to it.
Physical selection of RAM modules
For general development, it does not hurt to find out what modules the RAM chip itself consists of. So, here are all its main components:
Criteria for choosing RAM
If you have mastered the previous part, then we invite you to read about the criteria for selecting RAM. First of all, you need to pay attention to what type of memory your motherboard basically supports (DDR1/2/3). You can find this out in three ways:
- Read the information from your board manufacturer.
- Open the system unit and see the model name.
- If you don't have those options, you can check your processor manual: it probably lists all motherboards compatible with it, so you can probably figure out the truth.
However, if you have a normal Internet connection, you can do it even easier: click on the "Run" item in the "Start" menu, and then enter the dxdiag command there. After a while, the diagnostic utility window will appear. The item “Computer Model” is important to you, in which the model of the motherboard is registered.
Other remarks
Then you should read the information from the processor manufacturer, find your model there and find out which types of RAM are most justified to use on a particular computer. In general, after that you can go to the store, where the necessary RAM is waiting for you. Its price, by the way, is quite high. So, even for a couple of gigabytes on an outdated DDR2 module, you can pay up to two thousand rubles. However, DDR3 is still much cheaper.
It should be noted that some people confuse the form factor of different types of RAM. For example, laptop RAM is called SO-DIMM, while desktops use full-size DIMM memory. As a rule, the first variety is also installed in monoblocks and (rarely) in compact PCs. Do not confuse when buying!
Here's what RAM is and what it's for in a computer.
Before choosing RAM for a computer, you need to clearly understand what it is in general.
Why "pull up"? Why not immediately take them from the hard drive? The fact is that the RAM is many times faster than even an SSD drive.
What data may soon be needed by the processor is determined by the operating system itself, automatically. She is very smart not to be talked about.
RAM types
When mammoths still walked the earth, the RAM was divided into SIMM and DIMM - immediately forget about these types of RAM, they have not been released or used for a long time.
Then DDR was invented (2001). There are also computers with this type of memory. The main difference from DDR2 and DDR3 is the number of contacts on the DDR memory board, there are only 184 of them. This type of RAM is much slower than its modern counterparts (DDR2 and DDR3).
DDR2 (2003) has a larger number of contacts (240 pieces), thanks to which the number of data streams has expanded and the transfer of information to the processor has noticeably accelerated. The maximum frequency of DDR2 is 1066 MHz.
DDR3 (2007) is the most common type of RAM in modern computers. Here they left the number of contacts alone (240 pieces), but made them electrically incompatible. Maximum DDR3 frequency - 2400 MHz . This type of memory is also characterized by lower power consumption and higher bandwidth.
DDR3 turned out faster than DDR2 by 15-20%.
DDR2 and DDR3 sticks have different "key" arrangements, they are not interchangeable...
RAM stick form factor
RAM sticks for laptops (SODIMM) and desktop computers (SDRAM) are different in size and appearance. For laptops, they look like this ...
... and for stationary home computers, something like this ...
This is where their differences (mostly) end. The characteristics that you need to know when choosing RAM are exactly the same for these two types.
RAM
In the last century, the amount of RAM was measured in kilobytes and megabytes (it’s even ridiculous to remember). Today - in gigabytes.
This parameter determines how much temporary information will fit into the RAM chip. Everything is relatively simple here. Windows itself consumes about 1 GB of memory during its operation, so there should be more of it in the computer.
2 GB - may be enough for a budget computer (movies, pictures, Internet)
4 GB - suitable for more demanding programs, games at medium and maximum quality settings
8 GB - "pull" heavy games at maximum quality settings or very memory-demanding programs *DANCE*
16 GB - the newest modern and heavy games will “fly”, as well as special professional monster programs *bb.* *gamer.*
32 GB - You have nowhere to put your money? Send them to me. %)
It is very important to take into account that ordinary 32-bit Windows operating systems "do not see" more than 3 GB of memory and, accordingly, do not use it. If you buy more than 3 GB of RAM, you MUST install a 64-bit system.
RAM frequency
Inexperienced users often, when choosing a RAM, are limited by its volume, but the memory frequency is no less important. It determines the speed at which data will be exchanged with the processor.
Modern conventional processors operate at 1600 MHz. Accordingly, it is desirable to buy memory with such a frequency, not higher (1866 MHz is possible). The difference between 1333 MHz and 1600 MHz is practically invisible "by eye".
As for memory sticks with a frequency of 2133 MHz and higher, they themselves cost wild money, for their full-fledged work you need special motherboards that cost wild money, and most importantly, you need a processor with an unlocked multiplier (supporting overclocking), which costs ... .
At the same time, all this disgrace will get very hot (you need a powerful cooling system (preferably water), which costs ...) and consume a lot of energy. This is the choice of crazy gamers.
By the way, the increase in computer performance with such overclocking will be only from 10 to 30%, and you will spend three times more money. Do you need it?
RAM timing
The “terrible” parameter of RAM, which few people know about and which is rarely taken into account when choosing memory, but in vain.
Latency (timing) is the time delay of a signal. It is measured in beats. Timings can take values from 2 to 13. The bandwidth of the "processor-memory" section and, as a result, the system performance depend on them, though quite a bit.
The lower the timing value, the faster the RAM works. For example, I purchased memory with timings of 9-9-9-24, but there are also faster ones, of course.
RAM timings can be adjusted in BIOS when overclocking the system (it is not recommended for inexperienced users to do this).
And at the end of the article, as promised at the beginning, I will tell you ...
How to properly install RAM in a computer
Before the procedure, be sure to turn off the computer and disconnect the power cord from the system unit.
No settings, after installing the memory, do not need to be made in the system. The system itself recognizes it and starts using it.
The easiest way to install memory is in a laptop (it can be more difficult to open the back cover). In laptops, the RAM is in a horizontal position, lies.
Just lift and pull it out of the grooves, insert a new one until it stops. The lock on the bar (slot) will not let you make a mistake when installing ...
On desktop computers, this process is a bit more complicated. The memory stands vertically to the motherboard and is clamped with latches.
To remove the bar, it is enough to spread these latches to the sides and it will “jump” out of the slot by itself. Installation will also take you 2 seconds - bring the bar to the slot, match the lock (slot) on the bar with the jumper in the slot and insert it all the way (hear a click - these latches will clamp the bar).
It is very important not to confuse the click of the clamps with the crunch of a broken motherboard.
This video shows the process in detail...
Dual channel memory mode
You also definitely need to install the brackets so that they work in two-channel mode. Usually the memory slots on the motherboard are painted in two colors - these are the channels ...
Thus, install your two sticks of RAM in slots of the same color. In our case - through one. If there is a lot of RAM (16 or 32 GB), then all the slots will be needed.
And a couple more words...
What brand of RAM is better to choose? According to world statistics, Kingston slats have the least defects and failures - draw a conclusion.
You can view all of the above characteristics of RAM in your computer using the Speccy program.
That's all for today. Up to new useful tips and computer programs.
RAM is used for temporary storage of data necessary for the operation of the operating system and all programs. There should be enough RAM, if it is not enough, then the computer starts to slow down.
A board with memory chips is called a memory module (or bar). Memory for a laptop, except for the size of the strips, is no different from memory for a computer, so follow the same recommendations when choosing.
For an office computer, one 4 GB DDR4 stick with a frequency of 2400 or 2666 MHz is enough (it costs almost the same).
RAM Crucial CT4G4DFS824A
For a multimedia computer (movies, simple games), it is better to take two DDR4 sticks with a frequency of 2666 MHz, 4 GB each, then the memory will work in a faster dual-channel mode.
RAM Ballistix BLS2C4G4D240FSB
For a mid-range gaming computer, you can take one 8 GB DDR4 bar with a frequency of 2666 MHz so that in the future you can add another one and better if it is a simpler running model.
RAM Crucial CT8G4DFS824A
And for a powerful gaming or professional PC, you need to immediately take a set of 2 DDR4 sticks of 8 GB each, while a frequency of 2666 MHz will be enough.
2. How much memory do you need
For an office computer designed to work with documents and access the Internet, one 4 GB memory bar is enough.
For a multimedia computer that can be used to watch high quality videos and undemanding games, 8 GB of memory is enough.
For a mid-range gaming computer, the minimum option is 8 GB of RAM.
A powerful gaming or professional computer requires 16 GB of memory.
More memory may be needed only for very demanding professional programs and is not needed by ordinary users.
Memory size for old PCs
If you decide to increase the amount of memory on an old computer, then please note that 32-bit versions of Windows do not support more than 3 GB of RAM. That is, if you install 4 GB of RAM, then the operating system will see and use only 3 GB.
As for 64-bit versions of Windows, they will be able to use all the installed memory, but if you have an old computer or have an old printer, then they may not have drivers for these operating systems. In this case, before buying memory, install the 64-bit version of Windows and check if everything works for you. I also recommend that you look at the website of the motherboard manufacturer and see how many modules and total memory it supports.
Also note that 64-bit operating systems consume 2 times more memory, for example, Windows 7 x64 takes about 800 MB for its needs. Therefore, 2 GB of memory for such a system will not be enough, preferably at least 4 GB.
Practice shows that modern Windows 7,8,10 operating systems are fully disclosed with 8 GB of memory. The system becomes more responsive, programs open faster, and jerks (freezes) disappear in games.
3. Types of memory
Modern memory is of the DDR SDRAM type and is constantly being improved. So DDR and DDR2 memory is already obsolete and can only be used on older computers. DDR3 memory is no longer advisable to use on new PCs, it has been replaced by a faster and more promising DDR4.
Please note that the selected memory type must be supported by the processor and motherboard.
Also, new processors, for compatibility reasons, can support DDR3L memory, which differs from regular DDR3 by a lower voltage from 1.5 to 1.35 V. Such processors will also be able to work with regular DDR3 memory if you already have it, but processor manufacturers do not recommend this from - due to increased degradation of memory controllers designed for DDR4 with an even lower voltage of 1.2 V.
Memory type for old PCs
Legacy DDR2 memory is several times more expensive than more modern memory. A 2 GB DDR2 stick costs twice as much, and a 4 GB DDR2 stick costs 4 times as much as a DDR3 or DDR4 stick of the same size.
Therefore, if you want to significantly increase the memory on an old computer, then perhaps the best option would be to switch to a more modern platform with a replacement motherboard and, if necessary, a processor that will support DDR4 memory.
Calculate how much it will cost you, perhaps a profitable solution would be to sell an old motherboard with old memory and purchase new, albeit not the most expensive, but more modern components.
The motherboard connectors for installing memory are called slots.
Each type of memory (DDR, DDR2, DDR3, DDR4) has its own slot. DDR3 memory can only be installed in motherboard with DDR3 slots, DDR4 with DDR4 slots. Motherboards that support the old DDR2 memory are no longer produced.
5. Memory specifications
The main characteristics of memory, on which its performance depends, are the frequency and timings. The speed of the memory does not have such a strong impact on the overall performance of the computer as the processor. However, you can often get faster memory for a fraction of the price. Fast memory is needed primarily for powerful professional computers.
5.1. Memory frequency
The frequency has the greatest effect on the speed of the memory. But before buying it, you need to make sure that the processor and motherboard also support the required frequency. Otherwise, the actual memory frequency will be lower and you will simply overpay for something that will not be used.
Inexpensive motherboards support a lower maximum memory frequency, such as 2400 MHz for DDR4. Medium and high-end motherboards may support higher frequency memory (3400-3600MHz).
But with processors, the situation is different. Older processors with DDR3 memory support may support memory with a maximum frequency of 1333, 1600 or 1866 MHz (depending on the model). For modern processors that support DDR4 memory, the maximum supported memory frequency may be 2400 MHz or higher.
6th generation Intel processors and above and AMD Ryzen processors support DDR4 memory at 2400 MHz or above. At the same time, their lineup includes not only powerful expensive processors, but also processors of the middle and budget class. Thus, you can build a computer on the most modern platform with an inexpensive processor and DDR4 memory, and in the future, change the processor and get the highest performance.
The main memory for today is DDR4 2400 MHz, which is supported by the most modern processors, motherboards and costs the same as DDR4 2133 MHz. Therefore, it makes no sense to purchase DDR4 memory with a frequency of 2133 MHz today.
What memory frequency is supported by a particular processor can be found on the manufacturers' websites:
By model number or serial number, it is very easy to find all the characteristics of any processor on the site:
Or just enter the model number in a Google or Yandex search engine (for example, "Ryzen 7 1800X").
5.2. high frequency memory
Now I want to touch on another interesting point. On sale you can find RAM at a much higher frequency than any modern processor supports (3000-3600 MHz and higher). Accordingly, many users are wondering how this can be?
It's all about the technology developed by Intel, eXtreme Memory Profile (XMP). XMP allows the memory to run at a higher frequency than the processor officially supports. XMP must be supported by both the memory itself and the motherboard. Memory with a high frequency simply cannot exist without the support of this technology, but not all motherboards can boast of its support. Basically, these are more expensive models above the middle class.
The essence of XMP technology is that the motherboard automatically increases the frequency of the memory bus, so that the memory starts to work at its higher frequency.
AMD has a similar technology called AMD Memory Profile (AMP) that was supported by older AMD motherboards. These motherboards usually supported XMP modules as well.
Buying more expensive memory with a very high frequency and an XMP-enabled motherboard makes sense for very powerful professional computers equipped with a top-end processor. In a middle-class computer, this will be money thrown to the wind, since everything will rest on the performance of other components.
In games, the memory frequency has little effect and there is no point in overpaying, it will be enough to take it at 2400 MHz, or at 2666 MHz if the price difference is small.
For professional applications, you can take a memory with a higher frequency - 2666 MHz, or if you want and funds allow for 3000 MHz. The difference in performance here is greater than in games, but not cardinal, so there is no point in overclocking the memory frequency.
Once again I remind you that your motherboard must support the memory of the required frequency. In addition, sometimes Intel processors become unstable at memory frequencies above 3000 MHz, while Ryzen has this limit around 2900 MHz.
Timings are delays between read/write/copy data operations in RAM. Accordingly, the smaller these delays, the better. But timings have a much smaller impact on the speed of the memory than its frequency.
There are only 4 main timings, which are indicated in the characteristics of memory modules.
Of these, the most important is the first digit, which is called latency (CL).
Typical latency for 1333 MHz DDR3 memory is CL 9, for higher clocked DDR3 memory CL 11.
Typical latency for 2133 MHz DDR4 memory is CL 15, for higher clocked DDR4 memory CL 16.
You should not buy memory with a latency higher than indicated, as this indicates a general low level of its technical characteristics.
Usually, memory with lower timings is more expensive, but if the difference in price is not significant, then memory with lower latency should be preferred.
5.4. Supply voltage
The memory can have a different supply voltage. It can be either standard (generally accepted for a certain type of memory), or increased (for enthusiasts), or vice versa, reduced.
This is especially important if you want to add more memory to your PC or laptop. In this case, the tension of the new strips should be the same as that of the existing ones. Otherwise, problems are possible, since most motherboards cannot set different voltages for different modules.
If the voltage is set to a bar with a lower voltage, then others may not have enough power and the system will not work stably. If the voltage is set to a bar with a higher voltage, then the memory designed for a lower voltage may fail.
If you're building a new computer, this isn't that important, but to avoid potential motherboard compatibility issues and future memory upgrades or replacements, it's best to choose standard voltage sticks.
The memory, depending on the type, has the following standard supply voltages:
- DDR - 2.5 V
- DDR2 - 1.8 V
- DDR3 - 1.5V
- DDR3L - 1.35 V
- DDR4 - 1.2 V
I think you noticed that DDR3L memory is on the list. This is not a new type of memory, but the usual DDR3, but with a reduced supply voltage (Low). This is the kind of memory needed for Intel 6th generation and above processors that support both DDR4 and DDR3 memory. But in this case, it is better to assemble the system on the new DDR4 memory.
6. Marking of memory modules
Memory modules are marked according to the type of memory and its frequency. The marking of DDR memory modules begins with PC, followed by a number indicating the generation and speed in megabytes per second (Mb / s).
This marking is inconvenient to navigate, it is enough to know the type of memory (DDR, DDR2, DDR3, DDR4), its frequency and latency. But sometimes, for example, on classifieds sites, you can see the markings rewritten from the bar. Therefore, so that you can navigate in this case, I will give the marking in a classic form, indicating the type of memory, its frequency and typical latency.
DDR - obsolete
- PC-2100 (DDR 266 MHz) - CL 2.5
- PC-2700 (DDR 333 MHz) - CL 2.5
- PC-3200 (DDR 400 MHz) - CL 2.5
DDR2 - obsolete
- PC2-4200 (DDR2 533 MHz) - CL 5
- PC2-5300 (DDR2 667 MHz) - CL 5
- PC2-6400 (DDR2 800 MHz) - CL 5
- PC2-8500 (DDR2 1066 MHz) - CL 5
DDR3 - obsolete
- PC3-10600 (DDR3 1333 MHz) - CL 9
- PC3-12800 (DDR3 1600 MHz) - CL 11
- PC3-14400 (DDR3 1866 MHz) - CL 11
- PC3-16000 (DDR3 2000 MHz) - CL 11
- PC4-17000 (DDR4 2133 MHz) - CL 15
- PC4-19200 (DDR4 2400 MHz) - CL 16
- PC4-21300 (DDR4 2666 MHz) - CL 16
- PC4-24000 (DDR4 3000 MHz) - CL 16
- PC4-25600 (DDR4 3200 MHz) - CL 16
DDR3 and DDR4 memory may have a higher frequency, but only high-end processors and more expensive motherboards can work with it.
7. Design of memory modules
Memory sticks can be single-sided, double-sided, with or without heatsinks.
7.1. Chip placement
Chips on memory modules can be placed on one side of the board (single-sided) and on both sides (double-sided).
It doesn't matter if you are purchasing memory for a new computer. If you want to add memory to an old PC, then it is desirable that the location of the chips on the new bar is the same as on the old one. This will help avoid compatibility issues and increase the likelihood of memory running in dual-channel mode, which we will discuss later in this article.
Now on sale you can find a lot of memory modules with aluminum heatsinks of various colors and shapes.
The presence of heatsinks can be justified on DDR3 memory with a high frequency (1866 MHz or more), since it heats up more. At the same time, ventilation must be well organized in the case.
A modern DDR4 RAM with a frequency of 2400, 2666 MHz practically does not heat up and the radiators on it will be purely decorative. They can even interfere, because after a while they will become clogged with dust, which is difficult to clean out of them. In addition, such memory will cost a little more. So, if you want, you can save on this, for example, by taking Crucial's excellent 2400 MHz memory without heatsinks.
Memory with a frequency of 3000 MHz or more also has an increased supply voltage, but it also does not get very hot, and in any case it will have radiators.
8. Memory for laptops
Notebook memory differs from desktop memory only in the size of the memory module and is labeled SO-DIMM DDR. As well as for stationary computers, memory for laptops has the types DDR, DDR2, DDR3, DDR3L, DDR4.
In terms of frequency, timings and voltage, memory for laptops does not differ from memory for computers. But laptops only come with 1 or 2 memory slots and have tighter limits on maximum capacity. Be sure to check these parameters before choosing memory for a particular laptop model.
9. Memory modes
Memory can operate in single channel (Single Channel), dual channel (Dual Channel), three-channel (Triple Channel) or four-channel mode (Quad Channel).
In single-channel mode, data is written sequentially to each module. In multichannel modes, data is written in parallel to all modules, which leads to a significant increase in the performance of the memory subsystem.
Single-channel memory mode is limited only by hopelessly outdated motherboards with DDR memory and the first models with DDR2.
All modern motherboards support dual-channel memory, and only a few very expensive motherboards support three-channel and four-channel memory.
The main condition for the dual-channel mode is the presence of 2 or 4 memory sticks. Three-channel mode requires 3 or 6 memory sticks, and four-channel mode requires 4 or 8 sticks.
It is desirable that all memory modules are the same. Otherwise, dual-channel operation is not guaranteed.
If you want to add memory to an old computer and your motherboard supports dual-channel mode, try to choose a bar that is as identical as possible in all respects. It is best to sell the old one and buy 2 new identical strips.
In modern computers, memory controllers have been moved from the motherboard to the processor. Now it is not so important that the memory modules are the same, since the processor in most cases will still be able to activate dual-channel mode. This means that if in the future you want to add memory to a modern computer, you will not necessarily look for exactly the same module, just choose the most similar in terms of characteristics. But still, I recommend that the memory modules be the same. This will give you a guarantee of its fast and stable operation.
With the transfer of memory controllers to the processor, 2 more modes of dual-channel memory operation appeared - Ganged (paired) and Unganged (unpaired). If the memory modules are the same, then the processor can work with them in Ganged mode, as before. If the modules differ in characteristics, then the processor can activate the Unganged mode to eliminate distortions in working with memory. In general, the speed of the memory in these modes is almost the same and does not make any difference.
The only downside to dual channel mode is that multiple memory modules are more expensive than one of the same capacity. But if you are not very tight on funds, then buy 2 bars, the memory speed will be much higher.
If you need, say, 16 GB of RAM, but you can't afford it yet, you can buy one 8 GB stick to add another one of the same in the future. But still, it is better to purchase two identical strips at once, since then you may not be able to find the same one and you will encounter a compatibility problem.
10. Manufacturers of memory modules
One of the best price / quality ratios today is the memory of the impeccably proven Crucial brand, which has modules from budget to gaming (Ballistix).
The well-deserved brand Corsair competes on a par with it, the memory of which is somewhat more expensive.
As an inexpensive but high-quality alternative, I especially recommend the Polish brand Goodram, which has bars with low timings for a low price (Play line).
For an inexpensive office computer, simple and reliable memory from AMD or Transcend will suffice. They have proven themselves perfectly and there are practically no problems with them.
In general, the Korean companies Hynix and Samsung are considered leaders in the production of memory. But now the modules of these brands are mass-produced in cheap Chinese factories, and there are a lot of fakes among them. Therefore, I do not recommend purchasing the memory of these brands.
An exception may be Hynix Original and Samsung Original memory modules, which are made in Korea. These planks are usually blue in color and are considered to be of better quality than those made in China and have a somewhat higher warranty. But in terms of speed characteristics, they are inferior to memory with lower timings from other quality brands.
Well, for enthusiasts and fans of modding, there are available overclocker brands GeIL, G.Skill, Team. Their memory is characterized by low timings, high overclocking potential, unusual appearance and is slightly cheaper than the well-known Corsair brand.
There is also a large assortment of memory modules on sale from the very popular manufacturer Kingston. Memory sold under the budget Kingston brand has never been of high quality. But they have a top HyperX series, which is well-deservedly popular, which can be recommended for purchase, but it is often overpriced.
11. Memory packaging
It is better to purchase memory in individual packaging.
It is usually of higher quality and is much less likely to be damaged in transit than unpackaged memory.
12. Increase memory
If you are planning to add memory to an existing computer or laptop, first find out what the maximum number of sticks and the total amount of memory your motherboard or laptop supports.
Also check how many memory slots are on the motherboard or in the laptop, how many of them are occupied and what brackets are installed in them. Better to do it visually. Open the case, take out the memory sticks, examine them and write down all the characteristics (or take a photo).
If for some reason you do not want to go into the case, then you can see the memory parameters in the program on the SPD tab. Thus, you will not recognize a single-sided bar or a double-sided one, but you can find out the characteristics of the memory if there is no sticker on the bar.
There is a base and effective memory frequency. The CPU-Z program and many similar ones show the base frequency, it must be multiplied by 2.
After you know how much memory you can increase, how many free slots and what memory you have installed, you can begin to explore the possibilities of increasing memory.
If all the memory slots are occupied, then the only way to increase the memory is to replace the existing strips with new larger ones. And the old strips can be sold on the classifieds site or exchanged at a computer store when buying new ones.
If there are free slots, then you can add new ones to the existing memory strips. At the same time, it is desirable that the new strips be as close as possible in terms of characteristics to those already installed. In this case, you can avoid various compatibility issues and increase the chances that the memory will work in dual-channel mode. To do this, the following conditions must be met, in order of importance.
- The memory type must match (DDR, DDR2, DDR3, DDR3L, DDR4).
- The supply voltage of all strips must be the same.
- All slats must be single sided or double sided.
- The frequency of all bars must match.
- All strips must be of the same volume (for dual-channel mode).
- The number of bars must be even: 2, 4 (for two-channel mode).
- It is desirable that the latency (CL) match.
- It is desirable that the bars are from the same manufacturer.
The easiest way to start the choice is with the manufacturer. Choose in the catalog of the online store strips of the same manufacturer, volume and frequency as you have installed. Make sure that the supply voltage matches and check with the consultant whether they are single-sided or double-sided. If the latency also coincides, then it's generally good.
If you couldn't find similar strips from the same manufacturer, then choose all the others from the list of recommended ones. Then again look for the strips of the required volume and frequency, check the supply voltage and specify whether they are single-sided or double-sided. If you could not find similar planks, then look in another store, catalog or classifieds site.
Always the best option is to sell all the old memory and buy 2 new identical sticks. If the motherboard does not support the required size brackets, you may have to buy 4 identical brackets.
13. Setting up filters in the online store
- Go to the "RAM" section on the seller's website.
- Select recommended manufacturers.
- Select form factor (DIMM - PC, SO-DIMM - laptop).
- Select the type of memory (DDR3, DDR3L, DDR4).
- Select the required amount of strips (2, 4, 8 GB).
- Select the maximum frequency supported by the processor (1600, 1866, 2133, 2400 MHz).
- If your motherboard supports XMP, add a higher frequency memory (2666, 3000 MHz) to your selection.
- Sort the selection by price.
- Sequentially view all positions, starting with the cheapest ones.
- Choose a few bars that match the frequency.
- If the price difference is acceptable to you, go for the higher frequency, lower latency (CL) sticks.
Thus, you will get the optimal price / quality / speed memory for the lowest possible cost.
14. Links
RAM Corsair CMK16GX4M2A2400C16
RAM Corsair CMK8GX4M2A2400C16
RAM Crucial CT2K4G4DFS824A
And again, hello everyone! Today we will talk about RAM. What is working memory? What is it for? How it works? What types of RAM are there? What characteristics should you pay attention to when choosing it? You will find answers to these questions below in this article. And let's start in order.
What is working memory?
Random access memory - it is also RAM (Random Access Memory), RAM (random access memory), memory, RAM - a volatile part of a computer memory system in which executable machine code (programs) is stored during computer operation, as well as input, output and intermediate data processed by the processor.
Physically, the RAM module is embodied in the form of such strips that are inserted into a special slot on:
Here, in principle, I answered the first two questions. Although no, little is clear from this definition to the average person. But now we will analyze everything in detail. So.
There are several types of memory in a computer: energy NOT dependent and volatile or temporary.
Non-volatile memory is any memory device that can store data whether it is powered or not. In a computer, this is . You can save a file on it, disconnect your computer from the network, and the next time you turn it on again, everything will remain in place.
Volatile memory is computer memory that needs constant power to store information. Such in a computer is RAM. Which means that if you turn off the power from it (turn off the computer), all the information stored in it will disappear. That is, every time you turn on the computer, its RAM is empty.
I think this is understandable. The next part of the definition answers our next question.
What is RAM for?
The question will be fair: why in addition to a hard disk, on which data is stored regardless of whether power is supplied to it or not, does a computer need an additional, so unreliable thing like RAM?
The fact is that in comparison with the speed of work, the speed of reading and writing to the hard disk is very small. And if the processor directly worked with it, then the performance of the computer would be very low.
RAM is much faster than a hard drive. If you do not take into account the various caches, then the RAM will be the fastest element in a computer device, after the central processing unit.
Thus, RAM is needed to increase the performance of the computer, due to the fact that it allows the latter to quickly receive the necessary data.
How does it all work?
When you start the computer, all the necessary data: the operating system kernel, drivers, various services and startup programs are loaded from the hard disk into RAM and from there the CPU takes them for processing. The processor also returns the results of its work to RAM and not to the hard drive. Every program, every window you open in any program on your computer resides in RAM. The central processor also works with it. And only when you save some results of your work, they are written to the hard disk.
To better understand, let's look at a simple example of creating a text document in Word.
When you click on the shortcut to launch the program, all the files necessary for its operation are loaded into RAM and after that the editor window appears on the computer monitor. When you start writing text, it is also in RAM, you just won’t find it on your hard drive. In order for the result of your work to be saved on it, it must be saved by clicking the button of the same name in Word. Everyone at least once had such that you write, write some text and suddenly closed the program or the computer turned off, and after turning it on again, your text disappeared. Precisely because the RAM has been reset to zero, and you have never bothered to save your creativity.
I think now you already understand what RAM is, why it is needed and how it works. Now let's move on to more practical things. Namely, we will consider the types of RAM and its main characteristics.
Types (types) of RAM
Nowadays, RAM can be of two types: static (SRAM) and dynamic (DRAM). Static RAMs are faster than dynamic RAMs due to their manufacturing technology, but at the same time more expensive. This type is often used as a processor cache. DRAM technology is used for mass production of RAM modules. And there are several types of such memory. The ones you can see right now:
- DDR SDRAM- synchronous dynamic memory with random access and double data rate ( D double D ata R ate S synchronous D dynamic R andom A ccess M emory) of the first generation;
- DDR2 SDRAM- second generation DDR SDRAM;
- DDR3 SDRAM- third generation DDR SDRAM;
- DDR4 SDRAM- fourth generation DDR SDRAM;
As you might guess, DDR SDRAM is the oldest type of RAM, which is now very difficult to find. DDR4 is the newest. By far the most common is DDR3. These types of memory differ in performance and appearance.
In order to inadvertently not be able to insert a bar with one type of RAM into a slot designed for another type, there is a special key (sawed) on the bar, and a protrusion in the slot on the motherboard in the same place. And each type of memory is different.
In addition, with this key, you will not be able to insert the RAM module in reverse.
The main characteristics of RAM
- RAM type. You need to know what type of RAM your motherboard supports: DDR, DDR2, DDR3 or DDR4. And move on from that.
- RAM. Here you need to build on your needs. As I wrote above, all running programs will be placed in RAM. Accordingly, the more RAM you have on your computer, the more programs you can use at the same time. However, I'll give you a little hint. For simple homemade or office computer will be enough 2 GB. For home multimedia can be installed from 4 GB of memory. If you have game computer or you often use "heavy" professional programs You can install from 8 or more GB of RAM.
- Clock frequency. The bigger, the better. But here you also need to make sure that the motherboard and processor support this frequency. Otherwise, if the frequency of the RAM is higher than that supported by the motherboard, the RAM will operate at lower frequencies, which will mean an overpayment for unnecessary performance for you.
- Timings. This is the delay between accessing the memory and until it issues the necessary data. Accordingly, the lower the delays, the faster the RAM will work.
On this I will finish. I tried to present the basic information on the RAM of a computer, which will be enough for an ordinary user to understand what RAM is, what it is for and how it works, its main characteristics. Feel free to ask me questions in the comments if you don't understand something.
