Internal ConnectorsThere are a number of connectors on motherboards for components such as power supplies, fans, and LED lights. Computer cases often have front panel ports (e.g., USB, FireWire, or audio ports) that need to be connected to the motherboard. These ports are connected to the motherboard's front panel connectors, which are also called headers. External ports that are not available on the motherboard are often added using expansion cards.FirmwareThe firmware on a motherboard is stored on integrated flash memory. Motherboards use one of two firmware implementations:
BIOS (Basic Input/Output System)UEFI (Unified Extensible Firmware Interface)Older motherboards stored the BIOS on removable, read-only memory (ROM) chips. CMOS BatteryThe CMOS battery is used to keep an accurate date and time, even when the motherboard has no power. In older motherboards, the CMOS battery was also used to retain BIOS configuration settings, which were stored in volatile memory called the CMOS chip.ChipsetThe chipsetis a group of chips that facilitates communication between the processor, memory, and peripheral devices. With chipsets:The memory controller and graphics controller are on the CPU.The remaining functionality is combined into a single controller chip. oIntel processors use the Platform Controller Hub (PCH).oAMD processors use the Fusion Controller Hub (FCH).The front-side bus is replaced by the Direct Media Interface (DMI).Support manualA motherboard's support manual is an excellent source of information. Support manuals contain technical specifications as well as diagrams that identify the motherboard's components. If you are missing a motherboard's support manual, check the manufacturer's website.Selecting a motherboard with the same form factor as the case and power supply is an easy way to assure compatibility. A typical motherboard includes the common connectors shown in the following diagram:
Repairing a motherboard is beyond the skill of most technicians and it is almost always cheaper and faster to purchase a new one. You might also need to replace your motherboard to add new features or to upgrade the processor. Use the following process when installing or replacing a motherboard:1.If you are replacing an existing motherboard, document the current CMOS settings. You might need these settings to configure the new motherboard.2.Install the CPU, heat sink, and memory before installing the motherboard in the case.3.Insert the I/O shield into the case.4.Fasten standoffs to the case, being sure to match the hole pattern on the motherboard. Thestandoffs prevent the motherboard circuits from touching the system case.5.Install the motherboard, securing it to the standoffs with insulated washers and screws.6.Connect the power and accessory cables: oConnect the ATX power cable and the CPU power cable.oConnect the CPU fan power cable.oConnect case wires (e.g., power switch, reset switch, and drive activity and powerlights).oConnect any case fan cables.7.Connect drives to SATA connectors.