Many readers always find it difficult to understand all kinds of hardware. In fact, as long as you know some basic knowledge and parameters of this kind of hardware, you can have a more rational understanding of computer hardware.

First look at the parameters to understand the CPU.

CPU is the abbreviation of CentralProcessingUnit (CPU), which is generally composed of logic operation unit, control unit and storage unit. The logic operation and control unit includes some registers, which are used to temporarily store data during the processing of data by the CPU. The main CPU indicators/parameters you need to pay attention to are:

1. Power frequency

The main frequency, that is, the clock frequency of CPU, is simply the working frequency of CPU. For example, we often say P4 (Bense) 1.8GHz, and this 1.8GHz( 1800MHz) is the main frequency of CPU. Generally speaking, the number of instructions completed in a clock cycle is fixed, so the higher the main frequency, the faster the CPU. Main frequency = external frequency x multiple.

In addition, it should be noted that AMD's AthlonXP series processors all have the nominal value of PR(PerformanceRating), such as Athlon.

XP 1700+ and 1800+. For example, the actual working frequency of Athlon is 1.53GHz.

The label of XP is 1800+, which is also displayed in the self-check screen of system startup, system properties of Windows system, WCPUID and other detection software.

2. External frequency

The external frequency is the external clock frequency of the CPU. The main external frequencies of motherboard and CPU are 66MHz, 100MHz and 133MHz. In addition, the more external frequencies that the motherboard can adjust, the higher the better, especially overclocking.

3. Frequency doubling

Frequency doubling refers to the multiple of the difference between CPU external frequency and main frequency. For example, the CPU of AthlonXP2000+ has an external frequency of 133MHz, so its frequency doubling is 12.5 times.

Step 4 connect

Interface refers to the interface between CPU and motherboard. There are two main types, one is card interface, called slot. The CPU of the card interface is inserted vertically into the motherboard like all kinds of expansion cards we often use, such as graphics cards and sound cards. Of course, there should also be corresponding slots on the motherboard, and the CPU of this interface has been eliminated at present. The other is the mainstream pin interface, called Socket. The CPU of Socket interface has hundreds of pins, which are called Socket370, Socket478, Socket462, Socket423 and so on.

cache

Cache refers to memory that can exchange data at high speed. It exchanges data with CPU before memory, so it is extremely fast, so it is also called cache. There are two kinds of cache related to the processor-L1cache, also called internal cache; And L2 cache, also known as external cache. For example, Pentium 4 "Willamette" core products adopt 423-pin architecture, 400MHz front-end bus, 256KB full-speed second-level cache, 8KB first-level tracking cache and SSE2 instruction set.

@ 1 internal cache (l 1 cache)

That is, we often say that the first-level cache. The built-in cache of CPU can improve the running efficiency of CPU. The capacity and structure of the built-in L 1 cache have great influence on the performance of CPU. The larger the L 1 cache is, the fewer times the CPU exchanges data with L2 cache and memory with slow access speed, and the operation speed is faster than that of a computer. However, cache memories are all composed of static RAM, and their structures are very complicated. Under the condition that the CPU die area cannot be too large, the capacity of L 1 level cache cannot be too large, and the capacity unit of L 1 cache is generally KB.

@2 external cache (L2Cache)

The external cache of CPU is relatively expensive, so the external cache of Pentium 4 Willamette is 256K, but the Celeron 4 with the same core is only128 K.

6. Multimedia instruction set

In order to improve the computer's application ability in multimedia and 3D graphics, many processor instruction sets came into being, among which the most famous three are Intel's MMX, SSE/SSE2 and AMD's 3DNOW! Instruction Set Theoretically, these instructions play a comprehensive role in strengthening many popular multimedia applications, such as image processing, floating-point operation, 3D operation, video processing and audio processing.

7. Manufacturing process

Early processors were all made with 0.5 micron technology. With the increase of CPU frequency, the original process can no longer meet the requirements of the product, so there are 0.35 micron and 0.25 micron processes. The finer the manufacturing process, the more electronic components are integrated per unit volume. At present, processor products made of 0. 18 micron and 0. 13 micron are the mainstream in the market. For example, Northwood core P4 adopts 0. 13 micron manufacturing process. In 2003, the CPU manufacturing technology of Intel and AMD will reach 0.09 mm. ..

8. Voltage (Vcore)

The working voltage of CPU refers to the voltage required for the normal operation of CPU, which is related to the manufacturing process and the number of integrated transistors. The lower the normal working voltage, the lower the power consumption and the less heat generation. The development direction of CPU is to continuously reduce the voltage required for normal operation on the basis of ensuring performance. Like the old core Athlon

The working voltage of XP is 1.75v, while that of AthlonXP with new kernel is1.65v. ..

9. Packaging form

The so-called CPU packaging is the last process in the CPU production process. Packaging is a protective measure to cure CPU chips or CPU modules with specific materials to prevent damage. In general, CPU can only be delivered to users after packaging. The packaging mode of CPU depends on the installation form of CPU and the integrated design of devices. Generally speaking, CPU installed in Socket socket is usually packaged in PGA (Grid Array), while CPU installed in Slotx socket is all packaged in SEC (Single-sided Plug-in Box). At present, there are packaging technologies such as PLGA (PlasticLandGridArray Ray) and Olga (OLGA(OrganicLandGridArray). Due to the increasingly fierce market competition, the current development direction of CPU packaging technology is mainly to save costs.

10. Integer units and floating-point units

Alu-arithmetic logic unit, which is what we call "integer" unit. Mathematical operations such as addition, subtraction, multiplication and division, and logical operations such as "OR, AND, ASL and ROL" are all performed in the logical operation unit. In most software programs, these operations account for most of the program code.

FPU(FloatingPointUnit) is mainly responsible for floating point operation and high precision integer operation. Some fpu also have the function of vector operation, while others have special vector processing units.

Integer processing ability is the most important embodiment of CPU operation speed, but floating-point operation ability is an important index related to CPU multimedia and 3D graphics processing, so for modern CPU, the strength of floating-point unit operation ability can better reflect CPU performance.

Second, look at the parameters to understand the motherboard.

Motherboard is a common platform for all computer accessories, so when you buy or use a motherboard, you must first know what the core functions of your motherboard are, what types of CPU, memory and graphics card are, and how many PCI devices you can support.

1. plate type

If the circuit board wants to be the main board on the computer, it needs to be made into different board types. Here is a brief introduction to the common motherboard types. AT board is one of the most basic board types, which is characterized by simple structure and low price. Its standard size is 33.2cmX30.48cm. The AT motherboard needs to be used with the power supply of the AT chassis, and the baby

AT is an improved motherboard with AT architecture. Its structural layout is more reasonable, and it can support AT/ATX power supply. However, due to the popularity of ATX architecture, it has also declined.

The atX board is like a large horizontal AT board, which is convenient for the fan of the ATX chassis to dissipate heat to the CPU, and many external ports on the board are integrated on the motherboard, unlike many COM ports and printing ports on the AT board, which are output by wiring. In addition, ATX has a micro.

ATX mini-board can support up to 4 expansion slots, which reduces the size, power consumption and cost.

NLX board, which is favored by brand manufacturers, looks like a motherboard with a graphics card inserted. It consists of two parts: one part is an ISA substrate with logic control chips and basic input and output ports, and the other part is an additional board with slots such as AGP, PCI and ISA. It can be inserted into the special port of the substrate like a graphics card, which can increase space and facilitate disassembly.

2. Core

Motherboard chipset is the core of computer motherboards and represents the main technical characteristics of motherboards. With the adoption of different motherboard chipsets, various computer motherboards support different functions. For example, the motherboard uses Intel's i845D motherboard chipset. The main change of i845D motherboard chipset compared with its predecessor i845 is that it provides support for mainstream DDR memory. Its main features are introduced in the motherboard manual. "The I845D chipset consists of i845D chip and ICH2 chip, which supports the Pentium 4 processor of Socket478 and supports 400MHz.

FSB (Front Side Bus) supports AGP4X, integrates AC97 sound effects, and supports ATA 100 hard disk transmission specification. "

3. Socket type

The CPU socket is where the processor is installed on the motherboard. The main CPU sockets are Socket370, Socket478, Socket423 and Socket. Socket370 supports processors such as PIII, New Celeron and CYRIXIII. Socket423 is used in the early Pentium 4 processor, and Socket478 is used in the current mainstream Pentium 4 processor. And sockets

A(Socket462) supports AMD's Duron, Athlon and other processors. In addition, the CPU socket type is Socket7 socket, which supports Pentium/Pentium MMX and K6/K6-2 processors. SLOT 1 slot supports PII or PIII and AMD.

SLOTA socket for ATHLON and so on.

4. Supported memory types

At present, the main memory used by everyone is SDRAM with line 168 and DDRSDRAM with line 184. SDRAM memory, 168 line, bandwidth of 64 bits, working voltage of 3.3v, supporting different specifications such as PC66/100/150; The main feature of DDR memory is that it can use the rising edge and falling edge of clock pulse to transmit data, so it can double the speed of DRAM without increasing the working frequency.

At present, DDR memory has several specifications, including PC1600/pc2100/pc2700/pc3200. For example, a motherboard specification indicates that it "supports two DDR memory slots with 184 pins, and can support 2GB of memory capacity." This sentence shows that it does not support SDRAM with 168 line, and it has two DDR memory slots, which can insert two DDR memories. In addition, as can be seen from other DDR texts, this motherboard can only support DDR memory of PC 1600/PC2 100 specifications.

5. Supported AGP slot types

Graphics card slots such as AGP 1X(266Mbps), AGP2X(533Mbps), AGP4X( 1066Mbps), AGPPro, AGP universal slot (1066Mbps) and AGP8X(2 133Mbps). For example, the AGPX graphics card slot can use the AGPX graphics card, but the AGPX graphics card on the AGPX graphics card slot cannot be used normally (note: there are also general AGP2X/4X slots).

So what kind of graphics card your motherboard supports is the key to your correct choice of graphics card. For example, a motherboard uses an AGP4X slot, so you can buy an AGP 1X/2X/4X graphics card for normal use.

Third, look at the parameters to understand the hard disk.

As we all know, hard disks on the market are mainly divided into IDE and SCSI. SCSI hard disk has the characteristics of high speed, large capacity and stable use, and is the vanguard of hard disk technology, but its price is too expensive, and it is mainly used in more professional occasions.

Although there is a certain gap between IDE hard disk and SCSI hard disk in Shang Tong, there is no doubt that the gap is getting smaller and smaller. The current IDE hard disk also has the characteristics of high speed, large capacity and low price, making it the first choice for home occasions.

IDE hard disks can be divided into 5.25, 3.5, 2.5, 1.8 inch hard disks according to their inner disk diameters. 2.3 and 1.8 inch hard disks are mainly used for notebook computers and other devices; Hard disks with diameters of 5.25 and 3.5 are mainly used on desktops, and now the most commonly used hard disks with diameters of 3.5 inches are on desktops.

1. Hard disk capacity

When we buy a hard disk, the first thing we ask is, how big is this hard disk? Answer: 40GB and 80GB refer to the capacity of the hard disk. Generally refers to the formatted capacity of the hard disk. The larger the hard disk capacity, the better.

Secondly, when selecting capacity, you can also give priority to the large products stored in each disk. The larger the storage per disk, the more advanced the technology, and the easier it is to control the cost. For example, for the same 40GB hard disk, if the storage of each disk is 10GB, it needs 4 disks with 8 heads, and if the storage of each disk rises to 20GB, it needs 2 disks with 4 heads. For the storage of each 40GB hard disk, only 1 disk and 2 magnetic heads are needed, which can save a lot of costs and improve the working stability of the hard disk.

2. The speed of the hard disk

This is also a matter of concern to everyone. It refers to the rotational speed of the spindle in the hard disk. At present, IDE hard disks on the market are mainly divided into 5400 rpm and 7200 rpm. In the case of similar capacity and price, you can give priority to 7200 rpm fast hard disk products.

3. Hard disk transfer rate

The transmission rate of hard disk is also one of the important parameters of hard disk. Mainly refers to the transmission rate of external and internal data of hard disk, and their units are Mb/s (megabits per second) or MB/s( 1MB=8Mb). The burstdatatransferrate of hard disk is the burst data transfer rate of hard disk, which generally refers to the data interface speed of hard disk. At present, the hard disk transmission rate of ATA/66/ 100/ 133 interface can reach 66-133 MB/s.

The internaldatatransferrate of hard disk refers to the maximum data transfer rate between the magnetic head and the hard disk cache. In this respect, the maximum internal data transfer rate of mainstream hard disks on the market can generally reach more than 350Mb/S, and the maximum internal data transfer rate of excellent hard disks can reach 500 MB/s.

4. Hard disk cache

The cache size of hard disk is also one of the important indicators of hard disk. The cache of hard disk refers to the high-speed memory inside the hard disk. At present, most cache types used in hard disks are SDRAM, but there are exceptions, such as using EDODRAM. The larger the cache capacity, the better, which is directly related to the reading speed of the hard disk. At present, the cache capacity of hard disks is mostly 2M, and it is moving towards 8M. However, there are a few products with only 5 12K cache, so you should pay attention.

5. Hard disk head

There are two main types of magnetic heads used in hard disks: MR and GMR. GMR giant magnetoresistive head has begun to replace MR head as the mainstream of hard disk head.

MR magnetoresistive head adopts a head structure with separate reading and writing heads. It senses the signal amplitude through the change of resistance value, which is quite sensitive to the change of signal and improves the accuracy of reading data accordingly. Moreover, because the signal amplitude read by Mr magnetoresistive head has nothing to do with the track width, the track can be made very narrow, thus improving the density of the disk and making the capacity of the hard disk very large.

Compared with MR head, GMR head adopts materials with better magnetoresistance effect and multi-layer thin film structure, which is more sensitive than MR head, so it can achieve higher storage density. At present, the disk storage density of MR head can reach 3Gbit-5Gbit/in2 (per square inch per gigabit), and that of GMR head can reach more than 10 gbit-40 gbit/in2.

6. Hard disk seek time

Hard disk seek time is also one of the important parameters to understand hard disk. Mainly refers to averageseektime, singletrackseek time, maxfullseek time, averagelatency, etc. Are all in ms (milliseconds).

Average seek time of hard disk refers to the time required for the hard disk head to move to the track where the data is located. The smaller the number, the better. At present, the average seek time of IDE hard disk is mostly below 9 ms .. The seek time between tracks of hard disk refers to the time when the head moves from one track to another, and the shorter the time, the better.

The maximum seek time of hard disk refers to the total time it takes for the hard disk head to move from the beginning to finally find the required data block, and its value is as small as possible. The maximum seek time of mainstream IDE hard disks in the market is mostly within 20 ms As for the average waiting time of hard disks, it refers to the time when the head moves to the track where the data is located, and then waits for the required data block to continue rotating under the head. The smaller the number, the better.

Fourth, look at the parameter identification display.

The importance of display is self-evident, so what should we know?

1. cathode ray tube display

Visible area

The visible area refers to the maximum range in which the display can display graphics. We usually say 15 inch/17 inch actually refers to the size of the picture tube, but the actual visible area is far from this size. The visual range of a 14 inch display is often only 12 inch, that of a 15 inch display is about 13.8 inch, and that of a 17 inch display is mostly about 16 inch. When buying a monitor, it is naturally cost-effective to choose a wide field of vision with a large visual range.

Dot spacing/pitch

Point distance is one of the most important technical parameters of CRT, and the unit is mm (millimeter), which refers to the linear distance between two nearest fluorescent points of the same color of CRT. The smaller the spacing between points, the better. The smaller the point distance, the clearer the graphics displayed on the display. At present, the display usually adopts a dot spacing of 0.28. In addition, there is a concept of horizontal point distance. The horizontal point distance of the picture tube with a distance of 0.28 points is 0.24.

There are two types of picture tubes: shadow mask and shadow mask. Grid spacing refers to the distance between parallel grids of cathode-ray tube. Shadow mask CRT and cathode grid CRT have their own advantages and disadvantages. The advantage of using shadow grid kinescope is that its grid spacing will not be deformed after long-term use, and even after years of use, the picture quality will not decline. On the other hand, because the shadow grid can transmit more light, it can achieve higher brightness and contrast, making the image more vivid, realistic and natural.

Resolution; solve

Resolution defines the resolution of the display. As long as the bandwidth of the display is greater than the acceptable bandwidth at a certain resolution, this resolution can be achieved. Usually expressed by product, it represents the number of pixels in the horizontal direction (horizontal resolution) and the number of pixels in the vertical direction (vertical resolution), such as 800X600dpi, 1024X768dpi, etc.

The resolution of the display is affected by the size of the display, the spacing of picture tubes, the circuit characteristics and other factors. It is worth mentioning that the resolution that the display can achieve at a refresh frequency above 75Hz is its real resolution. At present, the maximum resolution of some manufacturers' advertisements is often the maximum resolution that can be achieved under the condition of extremely low refresh frequency, which generally cannot provide stable images above 75Hz, which is of little significance.

refresh rate

The refresh rate refers to the speed at which the display screen is refreshed, and the unit is Hz. The lower the refresh frequency, the worse the flicker and jitter of the image, and the faster the eye fatigue. Generally speaking, if the refresh frequency is above 80Hz, the flicker and jitter of the image can be basically eliminated.

The horizontal refresh rate, also called Horizontaiscanningfrequency, is the number of times the display scans the horizontal line within 1 second, and the unit is kHz. Vertical refresh rate, also known as Verticalscanningfrequency rate, is in Hz, which is determined by horizontal refresh rate and screen resolution. The vertical refresh rate indicates the number of times the screen image is redrawn per second, that is, the number of times the screen is refreshed per second.

Video bandwidth (bandwidth)

Bandwidth refers to the frequency range that a specific electronic device can handle, which determines the information range that a display can handle. Video bandwidth refers to the total number of pixels scanned by the electron gun per second, and the unit is megahertz (MHz). Theoretically, video bandwidth is the product of horizontal resolution, vertical resolution and vertical refresh rate. The wider the bandwidth, the higher the frequency that can be processed and the better the image quality. The video bandwidth gap between professional monitors and ordinary monitors is huge. The higher the bandwidth, the more expensive the monitor. The bandwidth of high-end monitors can reach more than 200MHz, but the bandwidth of daily household monitors is about 100MHz, which can meet our needs.

2.LCD display

Understand LCD mainly from the following points:

Brightness/contrast

The brightness of LCD is measured in square candle (cd/m2) or nits (lumens). Because LCD has more backlight than notebook, the brightness looks obviously brighter than notebook. Its brightness is generally between 150 nits and 500 nits. High brightness values certainly indicate high product performance.

However, it should be noted that some low-grade liquid crystal displays on the market have serious uneven brightness, and the brightness in the center is quite different from that in some areas of the frame. Therefore, everyone should pay more attention to the uniformity of brightness when purchasing LCD, that is, the display effect of this product requires uniform brightness in the center or four sides of the screen, and there is no obvious dark light phenomenon in the four sides, which should be paid attention to when purchasing LCD.

Contrast is a parameter that directly reflects whether LCD can reflect rich color levels. The higher the contrast, the better the layering of the restored picture. Even if you look at high-brightness photos, the dark details can be clearly reflected. At present, the contrast of liquid crystals on the market is generally between 150: 1 and 350: 1, and the high-end liquid crystals are higher. In the case of similar prices, we should first consider choosing products with higher contrast.

visible angle

Because LCD uses light transmission to develop images, there is a viewing angle problem, so ordinary LCD has a disadvantage that the viewing angle is small. In LCD, both direct light and oblique light will penetrate the pixels in the same display area, so when you look at the screen from an angle larger than the viewing angle, you will find that the image has ghosting and discoloration. Therefore, the viewing angle refers to the maximum angle at which the LCD image can be clearly seen, and the larger the viewing angle, the better.

Usually, the viewing angle of LCD is symmetrical, but it is not necessarily symmetrical up and down. At present, the horizontal viewing angle of 15 inch liquid crystal on the market is generally above 120 degrees, while the vertical viewing angle is much smaller than the horizontal viewing angle, and the horizontal asymmetry is generally above 95 degrees.

Response time

Signal response time refers to the time required for a pixel to change from bright to dark and then from dark to bright. The response time reflects the speed at which each pixel of the LCD responds to the input signal. The smaller the number, the better. In the past, the response time of most liquid crystal displays was between 20 and 100 milliseconds, but the new model can be realized within 20 milliseconds ... The shorter the response time, the less the moving picture will make the user feel like a tail shadow.

The simple way to judge is to move the mouse quickly. On the general low-grade LCD, when the cursor moves quickly, it will disappear in the process, and it will reappear only after the mouse is positioned and motionless for a short time. In the general speed action, you can also clearly see the traces of mouse movement during the movement. These have a great influence on you when you play action or 3D games or watch VCD. The liquid crystal with slow signal response will appear obvious image tailing and "ghost", which will seriously affect the display effect. In addition to reading the indicators given in the product manual or leaflet, the actual test is the most important.

measure

The size of the display is the diagonal length of the picture tube, and its unit is inches (1 inch =2.539 cm), while the size of LCD is different from that of CRT display, and its size is generally the real display size. At present, the main sizes of LCD on the market are 13.3, 14, 15, 17 and 17.

resolution ratio

Unlike CRT monitors, the resolution of LCD is fixed, and the picture quality is the best only at the specified resolution. At other resolutions, pictures can be displayed in an enlarged or compressed way.

When displaying a picture with a resolution lower than the optimal resolution, LCD displays it in two ways, one is centered display. For example, when the resolution of 800*600 times is displayed, the display only displays the picture with 800*600 pixels in the middle, with shadows around it. This makes the picture clear because the signal resolution is one-to-one, and the only regret is that the picture is too small.

Another way is to enlarge the picture of 800*600 to the resolution of 1024*768 by calculation. Because the signals and pixels processed in this way are not in one-to-one correspondence, although the picture is very large, it also causes image distortion, and the clarity and accuracy will be affected. At present, the best resolution of 14 inch/15 inch LCD is 1024*768, and the best resolution of 17 inch is 1280* 1024.

Five, look at the parameters to know the memory

With memory chips and less complicated processes, many manufacturers with a little strength can produce finished memory. In addition, you should also understand when purchasing or using memory.

1. Operating frequency

The working frequency of the memory is the standard specification of the memory. For example, the memory frequency of PC 100 standard is 100MHz, and the frequency of PC 133 is 133MHz. DDR memory is developed on the basis of SDRAM memory. Because it is based on the same frequency SDRAM, the bandwidth is twice that of the same frequency SDRAM. For example, when DDR266 memory runs at 133MHz, the actual working frequency is 266MHz and the bandwidth is 2.1GB/s/s.

If you want to buy a DDR333 memory, but the merchant gives you a DDR266 memory, the relatively simple and feasible method is to know from the access time of DDR memory, such as -7 and -7.5 nanoseconds in DDR266 memory, -6 nanoseconds in DDR333 memory and -5 nanoseconds in DDR400 memory.

Compared with DDR, DDR's subsequent standard, DDRII, is more advanced. On the basis of double transmission of DDR data, it has developed into quadruple transmission of data, which is twice as fast as DDR! If it also works at the external frequency of 133MHz, and the working frequency is 532MHz/S, its bandwidth can reach 4.2 GB/s.

2.CAS value

As we all know, there is a CAS(ColumnAddress) in memory.

Gating (column address gating) delay time. When information is stored in memory, it is like a big table. All the information stored in the memory is located by rows and columns. CL refers to how many clock cycles it takes to find the corresponding position.

For SDRAM, there are generally two values of 2 and 3, while DDR memory can be divided into 2 and 2.5. The smaller the CAS value, the better, which means that the product with DDR memory value of 2 has better performance than the product with DDR memory value of 2.5. If you need a product with a CAS value of 2, then you should pay attention to that JS sells 2.5 as a product (it can be actually used or tested by in-memory testing software).

3. Remember to mark common sense

In addition, knowing the numbering knowledge of some DDR memory chips can also give you a better understanding of DDR memory. Let's take the DDR memory of the most common HY as an example to explain it for everyone:

HYXXXXXXXXXXXXXX-XX

123456789 10 1 1

1: factory logo representing HY.

2: is the memory type -5d:DDR SDRAM.

3. Process and working voltage -V: CMOS, 3.3V；; U:CMOS，2.5V

4. Chip capacity and refresh rate -—64:64MB, 4kref；; 66:64MB，2kref28: 128MB，4kref56:256MB，8kref 12

:5 12MB，8kref

5: Chip structure (data width) —4: x4 (data width 4 bit); 8:x8； 16:x 16； 32:x32

6: Number of banks-1: 2 banks; 2:4 Bank

7: I/O interface-1:sstl _ 3; 2:SSTL_2

8. Chip kernel version-blank: first generation; A: The second generation; B: the third generation; C: the fourth generation

9: energy level-blank: normal; L: low energy consumption

10: packaging form-t: tsop; Q: TQFP；; l:CSP(LF-CSP)； F: FBGA

1 1: working speed-33: 300mhz; ; 4:250 MHz； 43:233 MHz； 45:222 MHz； 5:200 MHz； 55: 183 MHz； KDR266AHDR266BLDR200

Sixth, look at the parameter identification graphics card.

1. Core frequency

The core frequency of the graphics card is the default working frequency of the graphics card, and the higher the value, the better. For example, ATI's RV250(Radeon9000/9000Pro) adopts a manufacturing process of 0. 18 micron, which can handle four parallel rendering pipelines up to 1 100 million pixels per second.

The 9000 and 9000Pro are completely similar except for the core frequency. Radeon9000 is equipped with a core frequency of 250MHz.

GPU and 400MHzDDR memory (200MHz*2), while the core/memory frequency of 9000Pro is 275MHz/550MHz.

DDR(275MHz*2), so the latter has higher performance.

2. About video memory

Video memory is one of the most important factors affecting the performance of graphics cards.

Capacity of video memory

Speaking of video memory, you can definitely see that this graphics card is 16M, that is 32M, and so on, all referring to the capacity of video memory. Video memory is like a big warehouse, which contains data information, including frame buffer, Z buffer and texture buffer, which all occupy the capacity of video memory and increase with the improvement of picture resolution and color depth, so the capacity of video memory affects the performance of graphics cards.

Video storage speed

Memory speed refers to the working frequency of memory, which is expressed in nanoseconds on memory particles and generally includes 6ns, 5ns, 4ns, 3.5ns, 3ns, etc. Memory working frequency = 1/ memory speed, for example, 5ns memory working frequency = 1/5ns=200MHz.

Bit width and bandwidth of video memory

As we all know, the information in video memory is not static, and it needs to exchange data with the graphics card core (GPU or VPU) constantly, which involves the concept of video memory bit width. Memory bit width refers to the interface bit width of memory particles for data exchange with the outside world, which is generally 8bit, 16bit, 32bit, etc.

The bandwidth of video memory is the maximum data exchange provided by video memory per second. As we know, the data calculated by GPU of graphics card should be exchanged with video memory, so if the bandwidth of video memory is not high enough, it will seriously affect the performance of graphics card. Memory bandwidth is determined by memory bit width, memory frequency and memory particle number * * *, that is, memory bandwidth = memory bit width x memory frequency x memory particle number /8.

For example, the GeForceMX440SE graphics card uses hynix4nsDDRSDRAM memory with serial number Hy5dV "64"16 "22at. Judging from the serial number, it is 64 megabytes of memory particles, and the bandwidth of a single chip is 16 bits. If it uses eight memory chips, its memory capacity is 64 megabytes, which is as much as memory bandwidth. And if only four memory banks are used, the memory capacity is 32 megabytes, and the memory bandwidth is 16X4= 64-bit DDR.

3. Pixel filling rate

Pixel fill rate is a word we often hear when buying graphics cards. What is the pixel fill rate? The pixel filling rate is the number of points that the display chip/card can draw on the display every second.

For example, if you set the screen resolution to 800X600. Then each image on the screen needs 800X600=480000 pixels. and