- A small or large circuit board inside a cabinet containing most of the electronic components.
- Everything connected to the computer is directly or indirectly plugged into motherboard. Components like CPU, BIOS, ROM, RAM, chips, and CMOS setup information.
- Expansion slots for installing different cards like video, sound, graphics, and NIC.
- Also contains RAM slots, system chipset, controllers and underlying circuit to tie it together.
Types of motherboard
- Assemblies such as I/O port connectors, hard drive connectors, CD drive connectors etc installed as expansion boards.
- Takes lot of free space inside the case because of expansion slots.
- If something goes wrong such as bend or broken pin or defective controller can be repaired with minor cost.
- Are cheap and easy to produce.
- Most of the olden motherboards were non-integrated.
- Assemblies are integrated or built right onto the board.
- Serial and parallel ports, IDE, CD drive are directly connected to the motherboard.
- This tends to free some space inside case and better accessibility to the components.
- Cheaper to produce but are expensive to repair.
- Fast, powerful, feature rich motherboard at reasonable price.
Motherboard form factors:
- Determines general layout, size and feature placement on the motherboard.
- Form factors such as physical size, shape, component placement, power supply connectors etc.
- Various form factors of motherboards are AT, Baby AT, ATX, Mini-ATX, Micro-ATX, Flex ATX, LPX and Mini LPX and NLX.
1) AT (Advanced Technology):
- Oldest and biggest form factor and popular until Baby AT.
- Capable of using 386 processor.
- 12' inch size and was difficult to install, service and upgrade.
2) Baby AT:
- Standard in computer industries and still being used in Pentium class products.
- CPU socket is placed in such a way that it can interfere with longer bus cards.
- Limitation over peripheral card installation.
- I/O ports are connected to pin-outs near the floppy drive which results in jumbling of ribbon cables.
3) ATX (Advanced Technology Extended):
- Improvement done in easy to use, support for current and future I/O, and also to current and future technology.
- New mounting configuration for power supply.
- Processor relocated away from expansion slots to allow full length add-in cards.
- Provides air-flow through chassis and across the processor.
4) Mini ATX:
- Commonly same as ATX.
- Just change in size from ATX= 12" x 9.6" to Mini ATX= 11.2" x 8.2".
5) Micro ATX:
- Supports current and new processor technologies.
- AGP (Accelerated graphics port) to have high performance graphics.
- Smaller in size and less power supply.
6) Flex ATX:
- A subset of micro ATX.
- Gives chance to system developers to create new personal computer design.
- Enhanced flexibility to allow custom case and board design to be manufactured.
- Small motherboard size and supports current processor technology.
7) LPX (Low Profile Extension) and Mini LPX:
- Based on design by western digital.
- Usually found in desktop pc's.
- Case are slim-line, low profile case with riser card arrangement for expansion cards.
- Riser card arrangement means expansion boards are parallel rather than perpendicular.
- This make smaller case but limits number of expansion slots to two or three.
- High quality product at low cost but makes difficult to upgrade and repair.
8) NLX (New Low Profile Extended):
- Supports current and future processor technologies.
- Also supports new AGP and tall memory technology.
- Installing and upgrading the system is easy.
- First read the manual available with the motherboard.
- Now place the motherboard on proper position and screw it up tightly and also check whether it is touching to any metal anywhere.
- Plug in components like processor, CPU fan, RAM, hard disk, graphic card, power supply etc.
- Check all the connections are properly connected according to the manual and then test the motherboard.