Abbreviation of computer hardware terms

Hardware Terminology Interpretation Series-Motherboard

ATX/ miniature atx

To be exact, ATX and micro ATX are two industrial standards, which usually refer to the shape of the motherboard. As we know, the motherboard is a rectangular circuit board that integrates various electronic components and slots. In order to standardize the size and shape of the motherboard and the layout of various components, board standards such as AT, Baby AT, ATX and micro ATX have appeared.

ATX is the most common main board structure at present, which was put forward by Intel in July 1995. Miniature ATX, also known as Miniature ATX, is a simplified version of ATX structure. Compared with ATX, there are fewer expansion slots, so the shape is smaller, which can reduce the production cost. Simply put, from the appearance, the ATX motherboard is a "big board" and the micro ATX is a "small board".

Basic Input/Output System

BIOS is the abbreviation of "basic input and output system", that is, "basic input and output system". In fact, BIOS is a set of programs solidified on a ROM chip of the motherboard, which stores the most important basic input and output programs of the computer, system setup information, boot self-test programs and system boot bootstrap programs. To put it bluntly, BIOS is a "bridge" connecting software programs and hardware devices, which is responsible for solving the immediate needs of hardware. Key issues such as the stability and compatibility of motherboard performance largely depend on whether the BIOS management function on the motherboard is advanced.

Complementary metal oxide semiconductor

CMOS is the abbreviation of "complementary metal oxide semiconductor", which originally means "complementary metal oxide semiconductor memory" and is the raw material used to manufacture integrated circuit chips. But when we touch the motherboard, this "CMOS" refers to a battery-powered read-write RAM chip on the motherboard.

The relationship between BIOS and CMOS RAM is often confused. In fact, the correct explanation is that when you enter the BIOS to set hard disk parameters or other BIOS and save it, these settings will be stored in the storage area of CMOS RAM chip. Every time the system starts, the system will read the stored parameters from the CMOS RAM chip to decide how to configure the system. There is a connection between BIOS and CMOS RAM, but they are two completely different parts of the system.

direct memory access

DMA is the abbreviation of "direct memory access", which means "direct memory access" in Chinese. DMA is a high-speed data transmission mode, which allows direct reading and writing of data between external devices and memory. The whole process is under the control of DMA controller, without the participation of CPU. Besides doing some processing at the beginning and end of data transmission, CPU can also do other work during transmission, which greatly improves the working efficiency of the computer.

Hardware Terminology Interpretation Series-Graphics Card

1.2D/3D graphics acceleration

In the past, due to the limitation of the technical performance of display chips, all the data needed to be processed when computers display 2D/3D graphics were borne by the CPU. With the development of graphics chip technology, the graphics card began to undertake the display processing of all 2D graphics, greatly reducing the burden on the CPU and naturally improving the speed of graphics display, so there was a 2D graphics accelerator card. However, because the amount of data and various calculations needed to be processed when displaying 3D graphics far exceed that of 2D graphics display, the graphics card could not undertake the processing of 3D graphics display data before the emergence of 3D graphics processing chips.

2. Ramdac

At present, most computers are still equipped with traditional analog CRT (cathode ray tube) displays, and the brightness of the picture tube can only be controlled by the signal voltage amplitude. Therefore, RAMDAC (Video Storage Digital-to-Analog Converter) in the graphics card must process the display graphics chip, convert the digital display signal stored in the video memory into a video signal composed of three colors brightness and line frame synchronization signals frame by frame, and then pass through the 15 pin.

At present, RAMDAC chips are not installed independently on mainstream graphics cards, because manufacturers have already integrated RAMDAC into them when producing graphics cards.

Step 3 remember

The function of video memory is similar to that of system memory. System memory is used to temporarily store data processed by CPU, and video memory is used to temporarily store data processed by display chip. When processing data, the display chip not only needs the video memory, but also needs to send the data to the video memory again after processing, so the bandwidth and speed of the video memory will directly affect the running speed of the display chip.

Step 4 solve

Resolution, also called resolution, refers to the number of points drawn by the graphics card on the display screen, which is expressed in the form of "horizontal points × vertical points". For example, 800×600 means that there are 800 points in the horizontal direction and 600 points in the vertical direction.

5. Color depth

Color depth refers to the data width used to describe the color of each pixel at a certain resolution, and the unit is "bit". It determines the kind of color each pixel can have. For example, for an 8-bit color depth, a pixel can use the power of 256 colors. However, we usually refer to the result of power directly as color number instead of color depth, such as 256 colors, enhanced colors (16 color depth, 65536 color number, also called 64K color), true colors (24 color depth,16777216 color number), and so on. The more colors, the closer the described color is to the real color.

6. Refresh frequency

The refresh rate refers to the update speed of the image on the display, that is, the number of frames that the image appears on the screen every second. The higher the refresh rate, the smaller the flicker of the image on the screen, the more stable the image and the better the visual effect.

Hardware Terminology Interpretation Series-Memory Chapter

clock cycle

TCK is the abbreviation of "clock cycle time", that is, memory clock cycle. It represents the maximum working frequency that the memory can run. The smaller the number, the higher the frequency that the memory can run. At present, many manufacturers like to express this value by working time, so the clock period is inversely proportional to the working frequency of the memory, that is, TCK =1/f. For example, a memory chip marked with "-10" means that its running clock period is 10ns, which means that it can be at 100MHz.

access time

TAC (access time from CLK), access time. Unlike clock cycles, tAC only represents the time required to access data. Note that tAC and tCK are two completely different concepts. For example, a memory chip marked "-7J" does not mean that its clock cycle is 7ns, but that its access time is 7ns, and it cannot work at the frequency of 133MHz. When buying memory, you must distinguish the difference between these two parameters, and don't be fooled by JS.

CAS delay time

CL(CAS Latency) is an important index of memory performance, which is the response time of memory longitudinal address pulse. We can think of the memory stick as a warehouse divided into grids, and the data is stored in these grids. When the computer needs the data in the "warehouse", there is usually a "buffer period" before the actual reading, and the length of the "buffer period" is the above-mentioned "CL". It can be seen that when the CL of the memory is 2, its performance will be better than that when CL=3. Therefore, reducing the period of CAS is helpful to speed up the working speed of the memory at the same frequency.

memory bandwidth

Memory bandwidth, also known as "data transfer rate", refers to the maximum number of bits (or bytes) that can be accessed into memory every second. With the development of technology, the data processing ability of CPU, graphics card and other equipment is getting stronger and stronger. As a "bridge" for these devices, there is no big breakthrough in the bandwidth of memory. This small bridge can no longer meet the data transmission requirements of these devices, so the memory has become a bottleneck that hinders the improvement of system performance. As we know, the memory can only transmit the data requested by one data within a working time, and in the process of data transmission, if the bus width and clock frequency are fixed, the total time occupied by the bus depends on the data transmission volume and the bandwidth of the memory bus. So the bandwidth of memory will directly affect the storage system of PC. Simply put, if the memory is regarded as a big warehouse, then the gate of the warehouse can be regarded as the total bit width of the memory (the size of the total bit width is fixed and cannot be changed, for example, the total bit width of SDRAM is 64 bits), and each memory chip on the memory stick is a small door in the warehouse. If we plan to move things from the warehouse, we will find the following rules: the amount of goods that can be moved out or in at a time is directly proportional to the size of the warehouse door (total memory width). The bigger the door, the more small doors, and the greater the cargo throughput in natural unit time.

Memory bank

Simply put, BANK is the channel used to exchange data between the memory and the Northbridge chip on the motherboard. Take SDRAM system as an example, the interface bit width between CPU and memory (that is, CPU to DIMM slot) is 64 bits, which means that CPU will send or read 64 bits of data from memory at a time, so this 64-bit data set is a memory BANK, which is called Bank (physical bank) in the product descriptions of many manufacturers. The number of banks in a memory stick has nothing to do with whether the memory stick is single-sided or double-sided. PCB circuit can be designed as double-sided and single-sided, or all chips (16 chips) can be placed on one side (at least in theory). Some memory chips are physical banks on one side, and some are physical banks on both sides, so we can't generalize. To accurately know the actual number of physical memory banks in a memory bank, we only need to know the number and bit width of logical memory banks of a single chip and the number of chips on the memory bank. The sum of bit widths of each chip is a single physical library, and if it is 128 64MB, it is a dual physical library. The current chipset supports at most two physical banks. Therefore, it is impossible for memory vendors to produce more than two physical bans.

Hardware terminology explanation series-CD

CLV (constant linear velocity)

CLV means "constant linear speed", which means that the optical drive runs at a constant linear speed when reading data. CLV can make the length of the track arc read in unit time the same when the optical head moves from the inner ring to the outer ring by changing the rotation speed of the spindle motor, which will inevitably lead to different speeds of reading the inner ring and the outer ring. When the speed of CD-ROM drive is relatively high, frequent replacement of spindle motor will reduce the life of CD-ROM drive, so CLV technology is only suitable for low-speed CD-ROM drive.

Constant angular velocity

CAV is "constant angular velocity", and all optical drives using this technology run at constant angular velocity when reading data. The spindle motor of optical drive using CAV technology does not need to adjust the speed frequently, thus prolonging the life of the motor and improving the random reading performance of optical drive. However, because the distance swept by the laser head in the outer ring is longer than that swept in the inner ring at the same time, the speed of the optical drive can only reach its nominal maximum when it works in the outer ring.

PCAV (partially constant angular velocity)

PCAV means "constant angular velocity in this area", which absorbs the advantages of CLV and CAV. That is, when reading inner-loop data, it is read in CAV mode, and when reading outer-loop data, it is read in CLV mode. This not only saves cost, but also improves performance. At present, most high-speed optical drives on the market adopt this method.

firmware

Firmware translated into Chinese is "firmware", which is equivalent to the BIOS on the motherboard and graphics card. At present, most CD-ROMs, CD-RW and DVD-ROM have this solid. By refreshing the firmware of hardware, the performance and compatibility of hardware devices can often be improved, and even the purpose of upgrading can be achieved.

speed

X-fold speed optical drive often mentioned refers to the data transmission rate of CD-ROM/CD-RW, and the transmission rate of single-fold speed optical drive is 150KB/s, so the transmission rate of an ordinary 52-fold optical drive is 52x0150kb/s. Note that the meaning of speed multiple of DVD-ROM is different from that of CD-ROM drive, because

Artificial intelligence error correction

The so-called artificial intelligence fault-tolerant technology is to adopt a fuzzy control technology. By testing thousands of CDs with various defects, the reading situation of each CD is recorded by special software, such as eccentricity, scratches, weak laser reflection and other conditions that may cause the CD-ROM drive to fail to read data normally, and the correction scheme formulated for each situation is written into the firmware. This is equivalent to storing thousands of prescriptions for difficult diseases in the "brain" of the optical drive in advance. In the future, when the optical drive encounters the above-mentioned bad disk reading phenomenon, it will automatically use the pre-designed scheme to correct the error, which can suit the remedy to the case, thus greatly improving the accurate disk reading ability of the optical drive.