The motherboard is the PC's center of activity. All devices in a computer are in some way connected to the motherboard. It hosts the largest single collection of chips of any PC component and serves as the "street system" for the grid of wires that link all the components, making it possible for them to communicate.
After this lesson, you will be able to:
- Identify a motherboard and its functions.
- Locate and define the components of a motherboard.
- Safely remove and replace a motherboard.
Estimated lesson time: 15 minutes
The motherboard (one is shown in Figure 6.1) defines the computer's limits of speed, memory, and expandability. A computer needs more than just a CPU and memory. To accept input from the user, it needs devices, such as a keyboard and a mouse. It also needs output devices, like monitors and sound cards, to cope with the powerful graphics and sound capabilities of the programs available today. A computer also needs "permanent" storage devices, such as floppy disk drives and hard disk drives, to store data when it is turned off. It is the function of the motherboard to provide the connectivity for all these devices, as well as for the CPU, RAM, and support ICs.
Figure 6.1 Motherboard with CPU
The motherboard is usually the largest circuit board found inside the computer case. Motherboards come in a variety of shapes. One size does not fit all, and careful attention to size and location of mounting holes is required before installing a new motherboard in an older computer. A motherboard needs to fit in the space allotted for it, be secure in its mounts, be properly grounded, receive sufficient ventilation (for cooling of the CPU and other heat-sensitive components), and must not conflict with other hardware. When considering the purchase of a new motherboard (see Lesson 2: Replacing and Upgrading Chips in Chapter 4), keep these things in mind:
A motherboard comes with a variety of support chips soldered in place. The primary elements constitute the chip set and are designed to work with the CPU. These chips are highly complex and coordinated ICs that help the CPU manage and control the computer's system. When replacing a CPU, you must make sure that it is compatible with the chip set and supported by the motherboard. If not, the computer won't work. A basic chip set (see Figure 6.2) consists of a:
Figure 6.2 Motherboard with chip set
On a more modern motherboard, you will find chips to control things such as cache memory and high-speed buses. You will also find boards with fewer individual chips because the manufacturer has incorporated several functions into one chip.
Keep in mind that there is a wide range of features and costs to choose from when you select a motherboard. You will need to keep up to date on the types of processors, memory design, CPUs, and expansion slots available in order to recommend and obtain the right product for your customers.
The following points summarize the main elements of this lesson: