As we all know, the motherboard is the total platform for all computer parts. And below we will take you to a comprehensive understanding of the motherboard in the form of illustrations.
A motherboard diagram A motherboard is mainly composed of circuit boards and various components on it 1. PCB PCB printed circuit boards are indispensable for all computer boards. It is actually made of several layers of resin material bonded together, the internal use of copper foil alignment. General PCB circuit boards are divided into four layers, the top and bottom two layers is the signal layer, the middle two layers is the ground layer and the power layer, the ground and power layer in the middle, so that it will be easy to make corrections to the signal line. Some of the more demanding motherboards have circuit boards with 6-8 layers or more. How is the motherboard (circuit board) manufactured? The PCB manufacturing process begins with a PCB "substrate" made of glass epoxy resin (Glass Epoxy) or similar material. The first step in the production is to draw a light between the parts of the on-line wiring, the method is to use negative transfer (Subtractive transfer) of the way the design of the PCB circuit board line negative "printing" on the metal conductor. This technique involves laying a thin layer of copper foil over the entire surface and eliminating the excess. In the case of double-sided boards, both sides of the PCB substrate are covered with copper foil. To make a multilayer board, the two double-sided boards are "pressed" together with a special adhesive. The next step is to drill and plate the holes needed to connect the components on the PCB. After the holes are drilled by the machine according to the drilling requirements, the inside of the hole must be plated (Plated-Through-Hole technology, PTH). Plated Through-Hole technology (PTH) is a metal treatment inside the hole, which allows the internal layers of wiring to be connected to each other. Before plating is started, it is necessary to remove debris from the hole. This is because the resin epoxy produces some chemical changes when heated, and it will cover the internal PCB layer, so it must be removed first. Both the removal and plating actions will be done in the chemical process. Next, solder resist (solder resist ink) needs to be covered on the outermost layer of wiring so that the wiring will not touch the plated part. Then various component marking screens are printed on the circuit board to mark the location of each part. They should not cover any wiring or gold fingers, as this may reduce solderability or the stability of the current connection. In addition, if there are metal connections, the "gold fingers" are usually gold-plated to ensure a high quality current connection when inserted into the expansion slot. Finally, it's time to test. Testing the PCB for shorts or breaks can be done optically or electronically. Optical testing uses scanning to find defects in each layer, while electronic testing usually uses a Flying-Probe to check all connections. Electronic testing is more accurate at finding shorts or breaks, but optical testing makes it easier to detect problems with incorrect gaps between conductors. After the circuit board substrate is ready, a finished motherboard is on the PCB substrate as needed to equip a variety of large and small components - the first SMT automatic mounter will be IC chips and chip components "welded up, and then manually inserted into some of the machine can not do the job, through the wave / reflow soldering process will be inserted into the components firmly Fixed on the PCB, so a motherboard is produced. In addition, the circuit board to do in the computer motherboard use, but also need to be made into different board type. One of the AT board type is one of the most basic board type, which is characterized by simple structure, low price, its standard size of 33.2cmX30.48cm, AT motherboards need to be used in conjunction with the AT chassis power supply, has been eliminated. The ATX board type is like a large horizontal AT board, so that it is easy to ATX chassis fan for CPU cooling, and many of the external ports on the board are integrated into the motherboard, and not like the AT board on the many COM ports, print ports have to rely on wires to output. In addition ATX there is a Micro ATX small board type, it can support up to four expansion slots, reducing the size, reduce power consumption and cost. 2. North Bridge Chip Chipset (Chipset) is the core component of the motherboard, in accordance with the arrangement of the different locations on the motherboard is usually divided into the Northbridge chip and Southbridge chip, such as Intel's i845GE chipset consists of 82845GE GMCH Northbridge chip and ICH4 (FW82801DB) Southbridge chip; and VIA KT400 chipset by the KT400 Northbridge chip and VT8235 and other Southbridge chips (there are also single-chip products, such as SIS630/730, etc.), of which the Northbridge chip is the main bridge, which can generally be used in conjunction with the different Southbridge chip in order to achieve different functions and performance. The Northbridge chip generally provides support for CPU type and frequency, memory type and maximum capacity, ISA/PCI/AGP slots, ECC error correction, etc. It is usually located on the motherboard near the CPU slot, and is equipped with a heatsink due to the generally high heat generation of this type of chip.3. Southbridge ChipThe Southbridge chip is mainly used to connect with the I/O devices and ISA devices and is responsible for managing interrupts and DMA channels, and for managing the interrupt and DMA channels. Responsible for the management of interrupt and DMA channels, so that the device works more smoothly, which provides support for KBC (Keyboard Controller), RTC (Real Time Clock Controller), USB (Universal Serial Bus), Ultra DMA/33 (66) EIDE data transfer mode and ACPI (Advanced Power Management), etc., in the position near the PCI slot. 4. CPU socket CPU socket It is the place where the processor is installed on the motherboard. Mainstream CPU sockets are Socket 370, Socket 478, Socket 423 and Socket A. Socket 370 supports Socket A, Socket B, Socket C, Socket D, Socket E and Socket F. Socket 370 support is PIII and the new Celeron, CYRIXIII and other processors; Socket 423 for the early Pentium4 processor, and Socket 478 for the current mainstream Pentium4 processor. Socket A (Socket 462) is supported by AMD's Viper and Dragon processors. There are also types of CPU socket to support Pentium / Pentium MMX and K6 / K6-2 processors such as Socket7 socket; support for PII or PIII SLOT1 socket and AMD ATHLON used SLOTA socket and so on. 5. Memory slots Memory slots are used on the motherboard to install the memory of the place. Currently, the common memory slots are SDRAM memory, DDR memory slots, and other early EDO and non-mainstream RDRAM memory slots. It should be noted that different memory slots have different pins, voltages, and performance functions, and different memory cannot be used interchangeably in different memory slots. For 168 lines of SDRAM memory and 184 lines of DDR SDRAM memory, the main difference in appearance is that there are two notches on the gold finger of the SDRAM memory, while the DDR SDRAM memory has only one. 6. PCI slots PCI (peripheral component interconnect) bus slots are a type of localized bus introduced by Intel Corporation. It is a local bus introduced by Intel Corporation. It defines a 32-bit data bus and is scalable to 64-bit. It provides connection interfaces for graphics cards, sound cards, network cards, TV cards, MODEMs and other devices, and its basic operating frequency is 33MHz, with a maximum transfer rate of up to 132MB/s. 7. AGP slot AGP Graphics Accelerated Port (Accelerated Graphics Port) is an interface dedicated to 3D acceleration cards (3D graphics cards). It is directly connected to the motherboard's north bridge chip, and the interface allows the video processor and the system directly connected to the main memory, avoiding the formation of system bottlenecks through the narrow bandwidth of the PCI bus, increasing the speed of 3D graphics data transfer, and in the case of insufficient video memory can also be called the system's main memory, so it has a high transfer rate, which is the PCI and other buses can not be compared with it. AGP interface can be divided into AGP1X/2X/PRO/4X/8X and other types. 8. ATA interface ATA interface is used to connect the hard disk and CD-ROM drive and other devices and set up. Mainstream IDE interfaces are ATA33/66/100/133, ATA33, also known as Ultra DMA/33, which is a synchronous DMA protocol developed by Intel Corporation, the traditional IDE transmission using the data trigger signal on one side of the data transfer, while Ultra DMA in the transmission of data on both sides of the data trigger signal, so that it has a 33MB / S transfer speed. S transfer speed. ATA66/100/133 is developed on the basis of Ultra DMA/33, and their transmission speeds can be reversed to 66MB/S, 100M and 133MB/S, except that in order to achieve the speed of 66MB/S or so in addition to the support of the motherboard chipset, but also to use a dedicated ATA66/100 40PIN 80-wire dedicated EIDE cable. In addition, now many new motherboards such as the I865 series provide a Serial ATA that is, Serial ATA slot, which is a completely different from the parallel ATA new hard disk interface type, it is used to support the SATA interface hard disk, its transfer rate of up to 150MB/S. 9. floppy interface floppy interface **** there are 34 pins, as the name suggests it is used to connect the Floppy disk drive, it is shorter than the IDE interface shape. 10. power jacks and motherboard power supply part of the power supply socket mainly AT power socket and ATX power socket two kinds of motherboards have both sockets. AT socket has been used for a long time is now obsolete. The use of 20-port ATX power socket, using the anti-reverse design, not like the AT power supply, because the plug instead of burning the motherboard. In addition to this, in the power socket is generally near the motherboard power supply and voltage regulator circuit. Motherboard power supply and voltage regulator circuit is also an important part of the motherboard, it is generally composed of capacitors, voltage regulator block or transistor field effect tube, filter coils, voltage regulator control IC blocks and other components. In addition, the P4 motherboard there is generally a 4-port dedicated 12V power socket. 11.BIOS and battery BIOS (BASIC INPUT/OUTPUT SYSTEM) basic input/output system is a loaded with boot and self-test program of the EPROM or EEPROM integrated block. It is actually a set of programs that are solidified on the computer's ROM (read-only memory) chip, providing the computer with the lowest level and most direct hardware control and support. In addition to this, there is usually a battery component near the BIOS chip, which provides the current needed for the BIOS to boot. Common BIOS chip identification ROM BIOS chip on the motherboard is the only labeled chip on the motherboard, generally double-row inline package (DIP), generally printed on the top of the word "BIOS", in addition there are many PLCC32 package BIOS. early BIOS for the rewritable EPROM chip, the label on the top plays a role in the protection of the BIOS. Early BIOS is mostly rewritable EPROM chip, the label above plays a role in protecting the content of the BIOS, because UV irradiation will make the EPROM content is lost, so it can not be torn down casually. Nowadays, the ROM BIOS mostly uses Flash ROM (erasable programmable read-only memory), which can be rewritten by refreshing the program, making it easy to upgrade the BIOS. Currently the more popular motherboard BIOS on the market are mainly Award BIOS, AMI BIOS, Phoenix BIOS three types. The motherboards on the market have adopted this BIOS. AMI BIOS is the BIOS system software produced by AMI, developed in the mid-80s, it is adaptable to a variety of software and hardware to ensure the stability of the system's performance in the 90s after the AMI BIOS application less; Phoenix BIOS is a product of Phoenix, Phoenix BIOS is mostly used in high-grade original brand-name machines, and is also used in the motherboards. Phoenix BIOS is a product of Phoenix, Phoenix BIOS is used in high-grade original brand-name machines and notebook computers, the screen is simple, easy to operate, now Phoenix has merged with Award, *** with the launch of both marked BIOS products. 12. chassis front panel connector chassis front panel connector is used to connect the motherboard chassis power switch, system reset, hard disk power indicator and other wiring. Generally speaking, the ATX structure of the chassis has a total power switch wiring (Power SW), which is a two-pronged plug, it is the same as the Reset connector, shorted when pressed, open when released, press, the computer's total power supply is turned on, and then pressed to turn off. And the two-pronged connector for the hard disk indicator has a red line. On the motherboard, such pins are usually labeled IDE LED or HD LED, connecting the red line to one. After this line is connected, when the computer is reading and writing the hard disk, the light of the hard disk on the chassis will be on. The power indicator is usually a two- or three-pronged plug, using the 1 and 3 positions, with the 1 wire usually green. On the motherboard, the pins are usually labeled Power LED, and when connecting it, note that the green wire corresponds to the first pin (+). When it is connected, as soon as the computer is turned on, the Power LED stays on, indicating that the power has been turned on. The reset connector (Reset) should be connected to the Reset pin on the motherboard. The Reset pins on the motherboard work like this: when they are shorted, the computer restarts. The PC speaker is usually a four-pronged plug, but in fact only 1, 4 two wires, a line is usually red, it is connected to the motherboard Speaker pin. When connecting, pay attention to the red line corresponds to the position of 1. 13. External interfaces ATX motherboards have external interfaces that are uniformly integrated in the back half of the motherboard. Nowadays, motherboards are generally in line with the PC''99 specification, that is, with different colors to indicate different interfaces, so as not to get it wrong. General keyboard and mouse are used PS / 2 round port, just the keyboard interface is generally blue, the mouse interface is generally green, easy to distinguish. The USB interface is flat, can be connected to MODEM, CD-ROM drive, scanner and other USB interface peripherals. The serial port can be connected to the MODEM and the square port mouse, etc., and the parallel port is generally connected to the printer. 14. other major chips on the motherboard In addition to this there are many important chips on the motherboard: AC97 sound card chip AC''97 full name is Audio CODEC'97, this is a joint research and development and development of a number of manufacturers, such as Intel, Yamaha, an audio circuit system standard. This is an audio circuit system standard jointly developed and developed by Intel, Yamaha and other manufacturers. The AC97 sound card chips integrated on the motherboard can be mainly categorized into two types: soft sound card and hard sound card chips. The so-called AC''97 soft sound card, just integrated on the motherboard digital-to-analog signal converter chip (such as ALC201, ALC650, AD1885, etc.), and the real sound card is integrated into the North Bridge, which will increase the CPU workload a little. The so-called AC''97 hard sound card is a sound card chip integrated on the motherboard (such as the innovative CT5880 and support for 6-channel CMI8738, etc.), which provides independent sound processing, and ultimately outputs analog sound signals. This hardware sound card chip is relatively more expensive than the soft sound card in cost, but the CPU occupation is very small. NIC chips Nowadays, many motherboards have integrated NICs. Common integrated network card on the motherboard chip chosen by the main 10/100M RealTek 8100 (8139C/8139D chip) series of chips and VIA network card chips. In addition, some mid-range and high-end motherboards also contain Intel, 3COM, Alten and Broadcom's Gigabit NIC chips, such as Intel's i82547EI, 3COM 3C940, etc. (See Figure 18-3COM's Gigabit NIC chip). (See Figure 18-3COM 3C940 Gigabit NIC chip) IDE array chip Some motherboards use additional IDE array chips to provide support for disk arrays, which use IDE RAID chips mainly HighPoint, Promise and other companies to simplify the function of the product. For example, Promise's PDC20276/20376 series chips can provide support for 0, 1 RAID configuration, with automatic data recovery. High-end HighPoint RAID chips such as HighPoint HPT370/372/374 series chips, SILICON SIL312ACT114 chips, etc. I/O control chip I/O control chip (input/output control chip) provides management and support for parallel and serial ports, PS2 ports, USB ports, as well as the CPU fan. support. Common I/O controller chips include WINBOND's W83627HF, W83627THF series, etc. For example, its latest W83627THF chip provides good support for the I865/I875 chipset, and in addition to supporting the traditional functions of the keyboard, mouse, floppy disks, parallel ports, joystick control, etc., it also innovates with a variety of new features, such as The W83627THF provides over-voltage protection for Intel's next-generation Prescott core microprocessors in compliance with the VRD10.0 specification, which prevents microprocessors from being burned out due to over-voltage operation. In addition, the W83627THF's internal hardware monitoring functions have also been greatly enhanced. In addition to monitoring the temperature, voltage, and fan of the PC system and its microprocessor, the W83627THF also provides linear speed control and an intelligent automatic fan speed control system, which enables the motherboard to completely linearly control the fan speed and select whether the fan should run at a constant or constant speed, as compared to the general control method. This system allows the motherboard to control the fan speed completely linearly and choose whether to run the fan at a constant temperature or a constant speed. These two new features not only allow users to control the fan more easily and extend the life of the fan, but more importantly, minimize the noise caused by fan operation. Frequency Generator Chip Frequency can also be referred to as the clock signal, frequency plays a decisive role in the work of the motherboard. What we currently call CPU speed is actually the frequency of the CPU, such as P4 1.7GHz. Computer to carry out the correct data transmission as well as normal operation, there is no clock signal is not possible, the main role of the clock signal in the circuit is to synchronize; because in the process of data transmission, the timing have strict requirements, only in this way can ensure that the data in the process of transmission without error. Clock signal first set a benchmark, we can use it to determine the width of the other signals, in addition to the clock signal to ensure that the send and receive data synchronization between the two sides. For the CPU, the clock signal as a benchmark, all signal processing within the CPU to use it as a ruler, so that it determines the CPU instruction execution speed. The frequency of the clock signal serves to speed up all data transfer and increases the speed at which the CPU processes the data, which is why we overclock to increase the speed of the machine. To generate the clock signal on the motherboard, that requires a specialized signal generator, also known as a frequency generator. But the motherboard circuit consists of multiple parts, each part to complete a different function, and each part due to the existence of their own independent transmission protocols, specifications, standards, so they work normally at different clock frequencies, such as the CPU's FSB up to hundreds of megabytes, the I / O port clock frequency of 24MHz, USB's clock frequency of 48MHz, so so many groups of frequency outputs, it is not possible to So many groups of frequency output, it is not possible to design separately, so the motherboard are using a dedicated frequency generator chip to control. Frequency generator chip models are very diverse, and their performance varies, but the basic principle is similar. For example, the ICS 950224AF clock frequency generator is commonly used on the I845PE/GE motherboard clock frequency generator, through the BIOS built-in "AGP/PCI Frequency Lock" function to ensure that any clock frequency under the provision of the correct PCI/AGP crossover frequency, with the start of the "AGP/PCI Frequency Lock" function. With this "AGP/PCI frequency lock" function, the use of how high the system clock do not have to worry about the hard disk inside the valuable data, and do not have to worry about the security of the graphics card, sound card, etc., overclocking, only depends on the quality of the CPU and memory only. Second, the summary Finally, let us through a detailed big picture to the motherboard to a thorough annotation. 1 is the integrated sound chip, 2 is the I / O control chip, 3 is the optical drive audio socket, 4 is the external audio auxiliary socket, 5 is the SPDIF socket, 6 is the USB plug, 7 is the chassis was opened connector, 8 is the PCI slots, 9 is the AGP4X slot, 10 is the front of the chassis universal USB interface, 11 is the BIOS, 12 is the chassis panel connector, 13 is the south bridge chip, 14 is the IDE1 socket, 15 is the IDE2 socket, 16 is the power indicator connector, 17 is the clear CMOS memory jumper, 18 is the fan power socket, 19 is the battery, 20 is the floppy drive socket, 21 is the ATX power socket, 22 is the memory slot, 23 is the fan power socket, 24 is the Northbridge chip, 25 is the CPU fan bracket, 26 is the CPU socket, 27 is the 12VATX power supply socket, 28 is the second set of audio sockets, 29 is the PS/2 keyboard and mouse socket, 30 is the USB socket, 31 is the parallel-serial port, 32 is the game controller and audio socket, and 33 is the SUP_CEN socket. The motherboard is the center of the entire computer, all components and peripherals are connected to the processor through it, and communication, and then by the processor to issue the appropriate operating instructions to perform the corresponding operation, so understand the structure of the motherboard is very important for each learning computer, especially learning computer repair personnel. It is difficult to imagine a motherboard is basically divided into several parts, each part of what role can not be divided into people can successfully repair the computer. In this article, I will take an ASUS latest 800MHz FSB P4 motherboard to take you to specific insight into the motherboard's five organs