The main printed circuit board in a computer is called the motherboard. Other names for this central computer unit are system board, motherboard or printed circuit board.
Many major components that are critical to the function of the computer are connected to the motherboard. These include processors, memory, and expansion slots. The motherboard is directly or indirectly connected to every part of the PC. The type of motherboard installed in the PC has a great impact on the computer's system speed and expansion capabilities.
The main components of the motherboard and their functions
Central Processing Unit (CPU)
The CPU is also called the microprocessor and is the brain of the computer. It is responsible for obtaining, decoding and executing program instructions, as well as performing mathematical and logical calculations.
The processor chip is identified by the processor type and manufacturer. This information is usually engraved on the chip itself. For example, Intel 386, Advanced Micro Devices (AMD) 386, Cyrix 486, Pentium MMX, Intel Core 2Duo or iCore7.
If the processor chip is not on the motherboard, the processor socket can be identified as slot 1 to slot 8, LGA 775, etc. This can help you determine the appropriate processor for the socket.
Random Access Memory (RAM)
Random access memory (RAM) usually refers to a computer chip that temporarily stores dynamic data during work to enhance computer performance.
In other words, it is the workplace of the computer, in which the active programs and data are loaded so that the processor does not have to obtain them from the hard disk whenever it needs them.
Random access memory is volatile, which means that once the power is turned off, it will lose its contents. This is different from non-volatile memory (such as hard drives and flash memory), which do not require power to retain data.
When the computer shuts down normally, all data located in RAM will be returned to permanent storage on the hard drive or flash drive. At the next startup, the RAM starts to be filled with programs that are automatically loaded at startup. This process is called startup. Later, the user opens other files and programs that are still loaded in memory.
Basic Input/Output System (BIOS)
BIOS stands for Basic Input/Output System. BIOS is "read-only" memory, which consists of low-level software that controls system hardware and acts as an interface between operating system and hardware. Most people refer to the term BIOS as a device driver or driver. BIOS is essentially the link between computer hardware and software in the system.
All motherboards include a small piece of read-only memory (ROM) that is separate from the main system memory used to load and run software. On a PC, the BIOS contains all the codes needed to control the keyboard, display, disk drive, serial communication, and many other functions.
The system BIOS is a ROM chip on the motherboard, used for startup routines (boot process), used to check out the system and prepare to run the hardware. The BIOS is stored on the ROM chip because the ROM retains information even if the computer is not powered on.
Semiconductor Random Access Memory (CMOS RAM)
The motherboard also includes a small separate memory block made of a CMOS RAM chip, even if the PC is powered off, the memory is kept active by a battery (called a CMOS battery). This prevents reconfiguration when the PC is turned on.
CMOS devices require very little power to operate.
CMOS RAM is used to store basic information about PC configuration, such as:
Floppy and hard drive types
Information about CPU
memory size
Date and time
Serial and parallel port information
Plug and play information
Power saving settings
The other important data stored in the CMOS memory is the time and date, which are updated by the real-time clock (RTC).
Cache memory
The cache is a small piece of high-speed memory (RAM) that improves PC performance by preloading information from (relatively slow) main memory and passing it to the processor on demand.
Most CPUs have an internal cache (built into the processor), called the primary cache or main cache. This can be supplemented by an external cache installed on the motherboard. This is the secondary or secondary cache.
In modern computers, level 1 and level 2 caches are built into the processor chip. If the third cache is implemented outside the die, it is called a level 3 (L3) cache.
PCI slot
The expansion bus is the input/output path from the CPU to the peripherals, and is usually composed of a series of slots on the motherboard. The expansion board (card) is inserted into the bus. PCI is the most common expansion bus in PCs and other hardware platforms. The bus transmits signals between various components, such as data, memory addresses, power and control signals. Other types of buses include ISA and EISA.
The expansion bus enhances the functionality of the PC by allowing users to insert the adapter card into the expansion slot to add functions that are missing in their computer.
chipset
A chipset is a group of small circuits that coordinate the flow of data in and out of the key components of the PC. These key components include the CPU itself, main memory, auxiliary cache, and all devices on the bus. The chipset also controls the data flow between the hard disk and other devices connected to the IDE channel.
A computer has two main chipsets:
NorthBridge (also known as the memory controller) is responsible for controlling the transfer between the processor and RAM, which is why it is physically located near the processor. Sometimes called GMCH, it is used in graphics and memory controller hubs.
SouthBridge (also known as input/output controller or expansion controller) handles communication between slower peripherals. Also called ICH (I/O Controller Hub). The term "bridge" is often used to refer to a component connecting two buses.
Chipset manufacturers include SIS, VIA, ALI and OPTI.
CPU clock
The CPU clock synchronizes the operation of all parts of the PC and provides basic timing signals for the CPU. Using a quartz crystal, the CPU clock provides a constant flow of pulses to it, thereby bringing the microprocessor to life.
For example, a 200 MHz CPU receives 200 million pulses per second from the clock. The 2 GHz CPU gets 2 billion pulses per second. Similarly, in any communication device, a clock can be used to synchronize data pulses between the sender and the receiver.
The "real-time clock" (also known as the "system clock") tracks the time of day and provides this data to the software. The "time-sharing clock" periodically interrupts the CPU and allows the operating system to allocate time between active users and/or applications.
Switches and jumpers
DIP (dual in-line package) switches are small electronic switches on circuit boards that can be turned on or off like normal switches. They are very small, so they are usually turned over by sharp objects, such as the tip of a screwdriver, a curved paper clip or a pen tip. Please be careful when cleaning near DIP switches, as some solvents may damage them. The DIP switches are obsolete and you will not be able to find them in modern systems.
The jumper pins are small protruding pins on the motherboard. Jumper caps or bridges are used to connect or short-circuit a pair of jumper pins. When the bridge is connected to any two pins through a short-circuit wire, it completes the circuit and has achieved a certain configuration.
The jumper cap is a metal bridge that closes the circuit. Generally, the jumper is composed of a plastic plug that is mounted on a pair of protruding pins. Sometimes jumpers are used to configure expansion boards. By placing jumper plugs on different pins, the parameters of the circuit board can be changed.