Difference between CPU speed and RAM is clear to anyone familiar with computers, and both characteristics are the basis computing process... In this article, we will explain what these concepts are based on.
A computer is made up of several different components, and each of these components contributes to the functioning of the machine. People who assemble computers and people who have sufficient knowledge of the operation of a computer are well aware of the many differences between the components of a computer, but there are a huge number of people who do not understand such issues.
The very first thing anyone potential buyer computer wants to know about a computer, this is how powerful it is. There are several specifications that you should be familiar with when buying a computer to get an idea of the performance of your computer. The two most important components The parameters of the processor and RAM that determine the speed of the computer. If the values of one of these components are low, then the speed and performance of the computer will also be low.
What determines processor speed?
The processor clock speed is essential characteristic computer, on the value of which the speed of the calculation depends. Computer vendors list the processor clock speed on the first line of the specification. After all, this parameter actually determines the speed of the computer, and at the same time its price. Clock rates are indicated in hertz. Processor speed in the most powerful systems is 3 GHz or higher. Currently on the market there are models with frequencies ranging from 1.6GHz to the most powerful Intel Core i7, clocked at 3.9 GHz.
What is RAM?
Just the presence in the system of a fast and powerful processor not enough to qualify as a supercomputer. It is important for a high-performance system to have enough random access memory... Having enough RAM allows you to quickly and efficiently process massive amounts of data and better cope with multitasking. The more RAM, the faster processor can process the data that he put there earlier. Thus, the speed of a computer depends to a large extent on the amount of RAM.
Today there are systems equipped with 8 GB RAM modules, which is truly phenomenal. For regular user 2GB of RAM is more than enough. Smartphones and tablets that are currently available usually come with 1GB of RAM.
Any user usually performs several tasks on a computer, such as browsing the web, listening to music, editing HD videos and editing documents, and spreadsheets, play in computer games... Your computer needs to be equipped with a processor with a fast enough clock speed and plenty of RAM for the computer to handle any of these functions with ease.
Today it is difficult to find at least one apartment that does not have a computer. The popularity of computers is quite natural, because they can be used to solve a variety of tasks. At the same time, sometimes, the capabilities of the computer are not enough to cope with this or another task. In this case, almost everyone starts thinking about buying a new computer.
Going into a computer store and choosing new computer, we advise you to pay close attention to three such important components as: CPU, video card and RAM. When choosing a processor, there are 4 things to consider:
Number of Cores,
The frequency of each core,
Cache levels,
Bus frequency.
The performance of the computer depends on the frequency of the processor, respectively, the higher the frequency, the greater the performance. In the event that you plan to work on your computer with serious applications or play games that require high performance computer, we advise you to opt for the processor Intel Core i5 or i7.
A cache is called an intermediate buffer between the CPU and RAM. To date, there are 3 levels of cache memory. The fastest is level 1, 2 is considered intermediate, 3 is the slowest, despite this, its speed is higher than the speed of RAM. Processors with three or more cores use mainly the 3rd level of cache memory.
Bus frequency refers to the clock frequency with which data is exchanged between the processor and the computer bus. The best option is the frequency above 1600Mhz.
The video card is also selected depending on the tasks that are planned to be solved using a computer, the more and more difficult task, the more powerful it should be graphics card... For a computer of average performance, you can opt for a multimedia video card that supports DirectX11, the card must have at least 1 Gb of memory.
When buying RAM, you should find out its type, module size, clock frequency, throughput, latency. Remember that RAM should be compatible with your motherboard... Typically, a motherboard only works with one type of memory: DDR2 or DDR3. The leader in performance today is DDR3. This kind memory features high clock speed and lower power consumption.
A relatively new type of memory is DDR4, in terms of its characteristics this type of memory surpasses all existing ones, because DDR4 supports frequencies from 2133 to 4266 MHz. Mass sale is planned for this fall.
Among the devices and units that make up a computer, the most important for the execution of any program are the RAM and the central microprocessor, which we will call simply the processor for brevity. In RAM the executable program is stored along with the data belonging to it; the processor performs calculations and other actions described in the program.
The program is loaded into memory from a hard or flexible magnetic disk, where it is stored, by the operating system in response to entering the program launch command from the keyboard. The operating system, having loaded the program, and, if necessary, configuring it to run in the memory area where it got to, informs the processor of the starting address of the loaded program and initiates the process of its execution.
CPU reads the first program instruction from memory, finds in memory or in its registers the data necessary for its execution (if, of course, the command requires data) and, having completed the required operation, returns to memory or, possibly, leaves the result of its work in the registers (Fig. . 1.1).
Rice. 1.1. The interaction of RAM and processor.
After executing the first command, CPU moves on to the next, and so on until the end of the program. After completing the program, the processor will not know what to do next, so any program must end with commands transferring control operating system computer.
Computer random access memory is an electronic device consisting of a large number binary storage elements, as well as their control circuits. The minimum amount of information that can be accessed in memory is one byte (8 binary digits, or bits). All bytes of RAM are numbered starting from zero. The necessary bytes are found in memory by their numbers, which serve as addresses.
Some data (for example, character codes) require one byte to store; for other data this space is not enough, and for them 2, 4, 8 or else are allocated in memory more bytes. Usually pairs of bytes are called words, and fours - double words (Fig. 1.2), although sometimes the term "word" denotes any piece of machine information.
Rice. 1.2. Byte, word and double word.
When discussing the contents of a multibyte datum, you have to refer to its constituent bytes; these bytes are conventionally numbered from zero and are located (when they are displayed on paper) in ascending order of numbers from right to left, so that bytes with higher numbers are on the left, and bytes with lower numbers are on the right. The leftmost byte is usually called the most significant, and the rightmost byte is called the least significant. This order of bytes is associated with the usual form of writing numbers: in a multi-digit number, the most significant digits are indicated on the left, and the least significant ones on the right. The next number, if written after the previous one, will again start with the most significant digit and end with the least significant one. but in computer memory the data is arranged in a more natural order of continuous ascending byte numbers, and thus each word or double word in memory starts with its low byte and ends with the high one (Figure 1.3).
Rice. 1.3. Numbering of bytes in multibyte data.
Strictly speaking, only whole binary numbers since memory is made up of binary storage elements. To record other data, for example, characters or fractional numbers, coding rules are provided for them, i.e. representations in the form of a sequence of bits of one or the length. So, real number single precision occupies a double word (32 bits) in memory, in which 23 bits are allocated for the mantissa, 8 bits for the order and one more bit under the sign of the number. Programs working with this kind of data should, of course, know the rules for recording them and be guided by them when processing and presenting this data.
The binary number system in which all digital ones work electronic devices, inconvenient for a person. For the convenience of representing the binary contents of memory cells or processor registers, sometimes octal is used, and more often - hexadecimal system reckoning. For Intel processors the hexadecimal system is used.
Each digit of a hexadecimal number can take 16 values, of which the first 10 are indicated by ordinary decimal digits, and the last 6 are letters Latin alphabet from A to F, where A stands for 10, B for I, C for 12, D for 13, E for 14, and F for 15. In assembly language, hexadecimal numbers, to distinguish them from decimal, end with the letter h (or H) ... So 100 is decimal number, and l00h is hexadecimal (equal to 256). Since one hexadecimal digit requires four binary bits to be written into the computer's memory, the contents of a byte are described by two hexadecimal digits (from 00h to FFh, or from 0 to 255), and the contents of a word are described by four (from 0000h to FFFFh, or from 0 to 65535).
Beyond the cells random access memory, for storing data, storage cells located in the processor and called registers are also used. The advantage of registers lies in their high speed much larger than random access memory, and the disadvantage is that there are very few of them - only about a dozen. Therefore, registers are used only for short-term data storage. In MP 86 mode, which we are discussing here, all processor registers are 16 bits long, or 1 word (in fact, in modern processors their length is 32 bits, but in MP 86 only half of each register is used). Each register is assigned a specific name (for example, AX or DS), by which it can be accessed in the program. The composition and rules for using processor registers will be described in detail below, but here we will only touch on the purpose of segment registers, with the help of which the processor accesses the memory cells.
Seemingly for transmission processor addresses of a byte random access memory, it is enough to write its number into one of the processor registers. In fact, you cannot do this in a 16-bit processor, since maximum number(given or address), which can be written into a 16-bit register, is only 216 - 1 = 65535, or 64K-1, and we will be able to access only the first 64 KB of memory. In order to address any byte of memory using 16-bit numbers, the MP 86 provides for segment memory addressing, which is implemented using segment registers of the processor.
The essence of segment addressing is as follows. Memory access is carried out exclusively with the help of segments - logical formations superimposed on certain areas physical memory... The executive address of any memory cell is calculated by the processor by adding the starting address of the segment in which this cell is located, with an offset to it (in bytes) from the beginning of the segment (Fig. 1.4). This offset is sometimes referred to as a relative address.
Rice. 1.4. Formation of a physical address from a segment address and an offset.
The starting address of the segment minus the four least significant bits, i.e. divided by 16 is placed in one of the segment registers and is called a segment address. The very same starting address is stored in a special internal register of the processor, called the shadow register. Each segment register has its own shadow register; the initial address of the segment is loaded into it by the processor at the moment when the program enters the new value of the segment address into the corresponding segment register.
The procedure for multiplying a segment address by 16 (or, which is the same, by 10h) is a fundamental feature of the real mode, which limits the range of addresses available in real mode, 1 MB in size. Really, maximum value the segment address is FFFFh, or 64K-1, from which it follows that the maximum value of the starting address of the segment in memory is FFFF0h, or 1 MB - 16. However, we consider that any offset in the range from 0 can be added to the starting address of the segment. to FFFFh, then the address of the last addressed byte will be equal to 10FFEFh, which corresponds to 1 Mbyte + 64 Kbytes - 17.
The range of addresses generated by the processor is called the processor address space; as we can see, in real mode it slightly exceeds 1 MB. Note also that 20 binary digits, or 5 hexadecimal digits, are required to describe an address within 1 MB. The 8086 had exactly 20 address lines and could therefore not go beyond 1 MB; modern 32-bit processors, if they work in real mode, have a slightly larger (almost 64 KB) address space available. If the processor operates in a protected mode (using 32-bit registers), then its address space increases to 232 = 4 GB.
QUESTION 2. Hard disk and optical drive... Types, device, characteristics.
QUESTION 3. Design and main characteristics of CRT monitors.
QUESTION 4. Design and main characteristics of liquid crystal monitors.
QUESTION 5. Calibration of monitors.
QUESTION 6. Technology inkjet... The device and characteristics of inkjet printers.
QUESTION 7. Technology laser printing... The device and characteristics of laser printers.
QUESTION 8. Plotters. Purpose, device and characteristics of plotters.
QUESTION 9. Color proof. Color profiles devices.
QUESTION 10. Digital cameras. Types, device and main characteristics of cameras.
QUESTION 11. Digital video cameras. Types, device and main characteristics of video cameras.
QUESTION 12. Varieties and basic characteristics of scanners.
QUESTION 13. The principle of operation of touch screens.
QUESTION 14. Digital representation of color. Color models. Depth of color. Color management.
QUESTION 15. Tone and color correction images. Tools for evaluating color characteristics and color correction of images.
QUESTION 16. Scaling and transformation of images.
QUESTION 17. Improving the quality of images: removing noise and sharpening.
QUESTION 18. Methods of animation. Animation file formats.
QUESTION 19. Presentation of video information. Video standards.
QUESTION 20. Principles of video compression. Codecs (definition of what a codec is) (frame-by-frame, inter-frame)
QUESTION 1. Processor and RAM. Main characteristics.
Central processing unit (CPU; also central processing unit - CPU; English central processing unit, CPU, literally - central processing unit) - an electronic unit or an integrated circuit (microprocessor) that executes machine instructions (program code), the main part of the computer hardware or programmable logic controller. Sometimes referred to as a microprocessor or simply a processor.
Knowing the characteristics of the processor, you can decompose it into shelves and adequately assess the computing performance of the future system. That is why it is very important to have a good understanding of all the main characteristics of processors. This article will be an introductory material, which will list all the main parameters of the CPU with a short description of each. For a more detailed acquaintance with any characteristic, you just need to go to the necessary links, where in separate articles it will be described in detail about each of the points.
I'll make a reservation right away: I'll tell some, and remind some, one simple rule of complexity of characteristics. That is, conclusions regarding the performance of this or that processor cannot be approached from the point of view of just one characteristic. For example, the statement “the better the processor with the higher frequency” no longer works due to the emergence of the concept of multi-core and other factors. In the same way, you cannot choose a processor by the number of cores, because there are others at least important criteria... So, I highly recommend looking at all the characteristics and evaluating the processor in all parameters at once. So, let's, perhaps, be more specific, so we are approaching the specific main characteristics of processors.
1. Multi-core processor
This characteristic, over the past few years, has been one of the most important in the field of central processing units, but not decisive, as I mentioned above. The era of single-core processors has long passed, so now you should choose multi-core processors (you still have to try to find single-core ones). Accordingly, the number of cores must be selected for specific tasks. For example, for simple tasks in the form of office applications and surfing the Internet, a dual-core processor is more than enough.
But for such tasks as professional work with graphics, you need a processor with 4 or 8 cores - a lot is decided by a specific processor model and the specifics of tasks. You can read in detail about the very principles of multicore in the full article.
2. Processor technology
The technical process of production does not directly affect the performance of the processor when performing tasks, but there is one "but" here. An increase in the clock frequency or any other architectural changes are impossible without making changes to the current technical process, since within the same processor family on the same technical process, the margin for increasing the clock frequency is limited. In 2011-2012, processors with the 22nm technical process were released, and everything goes to a decrease in these indicators. In fact, 22 nm is the width of the base of the transistors on which processors are mainly built. It is logical that the smaller the width of the base of the transistor, the more they can be "shoved" onto the crystal, which means that the processor's performance will increase.
3. CPU clock speed
The most famous characteristic of processors is clock frequency... The frequency of the processor determines the number of calculations performed per unit of time, and the performance of the processor directly depends on it. The frequency of modern central processors ranges from 1 to 4 GHz, but you should not look only at the processor clock speed, you should pay attention to other parameters as well. Of course, the processor frequency is still important parameter, I recommend reading full article according to this characteristic.
4. The amount of cache memory
The cache of modern processors lends a lot to their performance. Cache is ultra-fast volatile memory that allows the processor to quickly access certain data that is frequently used.
There are several levels of cache memory:
The first level cache is the fastest, but its size is very limited;
The L2 cache is slightly slower, but at the same time slightly larger in volume.
Also with L3 cache, which is slightly slower than L1 and L2 caches, but still significantly faster than RAM. Now the size of the third level cache reaches 12-16 MB and more. The limited amount of cache memory is manifested in its high cost due to the complex production process.
5. Processor socket
A socket is a connector on the motherboard into which the processor itself is installed. Again, the socket is not a direct characteristic of the processor, but this factor is so important that we cannot help but recall it. It is very important that the processor socket and the motherboard socket coincide, because the processor that is positioned for the LGA 1155 socket will not work in any way on the motherboard with LGA socket 775, you need to remember this, and always check these parameters when selecting components. I highly recommend reading the full article on processor sockets.
Main characteristics of RAM, tips for choosing
Random access memory (RAM - Random Access Memory). This component is classified as Volatile memory (all data will be deleted when the power is turned off). During operation, RAM acts as a buffer between the disk drives and the processor, due to the significantly faster data read and write speed. Next, we will look at the main characteristics of RAM ...
The main factors when choosing RAM for a desktop computer are Performance and Price, which directly depend on each other. Let's look at what characteristics affect them and try to choose the optimal ratio. Basic parameters - Type, Volume, Frequency, Timings, Voltage, Manufacturer.
Types of random access memory. In the course of the evolution of RAM, its shape has changed, as well as the position and principles of interaction of chips. In fact, each such configuration is a separate type. I will not describe outdated SIMMs, DIMMs, DDRs and even the still popular DDR2, since they are practically not produced by anyone and it would be foolish to assemble a new computer using significantly outdated key components. Besides, older types of RAM are more expensive than modern ones due to their "rarity" :-) The only type that is relevant today is DDR3 (Third Generation Double Data Rate). Compared to the previous, second generation (DDR2), all DDR3 boards have better performance with significantly reduced power consumption.
The amount of RAM. Its relevance can be described as follows: During your work at the computer, a large amount of data (operating system files, running applications and games) are moved from disk drives into RAM for further processing by the processor and are stored there until you finish the work of these applications (or rather, they are not just stored, some of them are constantly migrating between the processor's cache and RAM at great speed). The volume of RAM itself does not give us any acceleration. It just shows how much data can be stored in it. When the RAM is full (for example, if many large applications are running + a toy + a browser, etc.), older data is transferred to a special place on the disk (paging file). It is at this moment that you can feel how the computer starts to "slow down, lag, freeze", etc. From this, we can conclude that the amount of RAM should not be less than the maximum total amount of Possible active applications. The total volume of RAM is equal to the soup of the volumes of each of its individual strips. That is, if you install two 1 GB RAM strips, then the total available volume will become 2 GB. For a budget (for example, office) computer, 2 GB will be more than enough. For a home (multipurpose) PC, 4-6 GB is optimal. (depending on the number of strips - 2 pieces, or 3 pieces, 2 GB each). For a modern gaming machine, I would recommend buying at least 6-8 GB. (So to speak, "For the future", since game developers are constantly "burdening" their brainchilds).
RAM frequency. In short, this is the bandwidth of the channels through which data is transmitted to the motherboard, and from there to the processor. The more - the better and more expensive. It is desirable that this parameter coincides with the permissible frequency of the motherboard. If the RAM, for example, has a frequency of 1600 MHz, and the motherboard has 1066, then your RAM will not be able to fully reveal its potential and will work at a lower frequency of 1066 MHz. Consider this parameter when choosing a motherboard.
RAM timings. In other words - latency or latency (Latency) of RAM. This parameter is characterized by the data delay time when switching between different modules of the RAM microcircuit. There are many of these parameters, but only 4 main ones are indicated in the specifications and descriptions:
2. RAS to CAS Delay
3. RAS Precharge Time
4. DRAM Cycle Time
Smaller values mean faster performance. But there is one problem: The higher the frequency of the RAM, the higher its timings. Therefore, you should choose the optimal ratio of these two parameters, based on the budget. There are, for example, special models from different manufacturers, the note to which says "Low Latency". This means that this model has less latency at higher operating frequencies. But they are much more expensive, so only gamers and overclockers will pay attention to them, for whom every extra drop of performance is more expensive than any money.
Voltage. Indicates the required voltage for stable operation of the RAM at standard frequencies and timings. The less - the better, but this parameter is important only for overclocking (overclocking), since with a significant overclocking or understating of timings, it is necessary to additionally increase the voltage proportionally ... which, in turn, is accompanied by an additional increase in the temperature of certain motherboard modules and a deterioration in stability. such a system. For this purpose, special models of random access memory are produced, labeled "LV" - Low Voltage.
RAM manufacturer. As with the choice of other components for a computer, it is worth giving preference to well-known manufacturers and models, with a lot of positive reviews. In this case, there will be the least likelihood of buying a defective copy and a longer warranty period.
· Click to enlarge 1_ram.jpg Additional attention should be paid to the question of the desired number of RAM modules. The fact is that depending on the model of the motherboard and the number of RAM connectors on it, the RAM strips can operate in different speed modes (Single, Dual, Triple - Single, Double, Triple). In order not to describe each of them for a long time, I will go straight to the conclusion. Count the total number of RAM slots on your motherboard. In standard desktop models, they can be: 4, 6, 8. Divide these numbers by 2 and get the minimum number of required planks for optimal speed. For example, if you have 4 slots, it means that in order to activate the optimal mode, you will need 2 or 4 strips of RAM from the same manufacturer and model. That is, you activate one or 2 "Dual" modes. To work in certain regime You must connect the modules to connectors of the same color (usually through one).
