PC MOTHERBOARDS

The motherboard is the board that contains the logic circuits that tie all parts of your PC together. It provides the connectors for the CPU, the memory, BIOS, CMOS, Video devices, sound devices, storage devices, chipsets, etc. in order to form an integrated set of components.

First, let me give you a list of WEB sites of motherboard manufacturers:

  1. www.micronics.com
  2. www.asus.com
  3. www.abit.com
  4. www.Aopen.com
  5. www.Soyo.com

I suggest than any item you purchase should be from a "brand-name" company. I don't know if the US Army policies provide for GSA contracts for components, or whatever. I also don't know if it is really economical to replace motherboards and other components; or if you should just purchase new computers. But, either way, we should be able to download BIOS updates, etc., over the Internet or WEB.

Illustration Courtesy of Micronics Computers,Inc.
This is a "Micronics "Stingray" System Board.

This illustration is just to show what a motherboard looks like. It has each of the following components, and a lot more. the problem is to tell you where each of them are:

  1. ISA Expansion Slots (4 - long black slots at upper left)
  2. PCI Expansion Slots (4 - mid length white slots in middle)
  3. Pentium II CPU Slot (long slot near right edge)
  4. Memory (SIMM) bank (4 white slots to right of PCI slots).
  5. Memory (DIMM) bank (2 gray/black slots to right of SIMM slots).
  6. CPU (Microprocessor)Slot - (lower right, 2nd from bottom)
  7. External Cache (L2) (integrated into Pentium II CPU)
  8. ROM Chip (BIOS Chip)
  9. Clock Oscillator
  10. and more
The above illustration is a real motherboard, a Micronics "Stingray" System Mother board. On older PCs, you may not be able to view all details. It has a socket for PentiumII 200/233/266 MHZ processors (long slot upper right corner); 4 16-bit ISA slots (left side), 4 32-bit PCI slots(white slots in center) and 1 shared PCI/ISA slot (right); 5 32 bit EISA slots (upper right - brown slots); 4 64-bit, 168-pin DIMM sockets (for a possible 1 GB maximum memory); and much, much, more.

The board shown provides 8 expansion slots! It also has a "Universal Serial Bus" port! It has a high speed CPU slot (233, 266, and 300 MHz), and serious memory and L2 cache available. These are selling points for the future.

The motherboard also contains other components such as BIOS chips, the CPU clock, cache chips, bus, etc. To see every detail, you will need to get a "User's Manual" for the specific motherboard you have, and to locate all components on the board. The bus is actually a set of circuits that run throughout the board and connect all the expansion slots, memory, and CPU, etc. together. This photo does not contain enough detail to specifically show you the bus.

Motherboards sizes are as follows:

  1. Standard AT = 12" w x 13.8" long
  2. Baby AT = 8.57" w x 13.04" long
  3. LPX = 9.0" w x 13.0 long
  4. ATX = 9.6" w x 12.00 long

Sizes are important if you are replacing an existing motherboard!

The ATX is the Intel specification released in July 1995. It has become the defacto industry standard for motherboards.

The following drawing will help you to visualize the bus:

The motherboard components serve specific functions:

  1. BUS - connects all the components of the computer and provides a path from device/controller to the next component.

  2. Expansion Slots - for connecting other devices/controller cards to the motherboard.

  3. Memory Slots - provides receptacles for adding additional memory chips (SIMMs, DIMMs, or other types of memory).

  4. ZIF Socket - provides a location to insert the heart of the computer - the CPU.

  5. BIOS Chip - provides a definition of the system for booting.

  6. USB Port - some newer machines will have a port for the Universal Serial Bus (USB) connection.

  7. Chip Set - controls most of the capabilities such as type of memory, I/O, etc.

Selling points for motherboards in a system you buy:

Purchasing Considerations

THINK ABOUT THE FUTURE - IF YOU CAN AFFORD IT. REMEMBER A DOLLAR SAVED MAY MEAN YOU PURCHASE A PRODUCT THAT WILL BE 'OLD TECHNOLOGY' VERY SOON.

Memory

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