The Computer Case
The computer case, or chassis, is usually constructed of metal, holds all the primary electronic components of the computer and most of the drives. The case provides access to other devices via ports and connectors, and protects the computer's delicate circuitry from possible damage and electromagnetic interference (EMI). It also protects surrounding devices, such as TVs, from the computer's EMI.
When recommending a computer for purchase, the size and configuration of the case should be considered.
- The bigger the case, the more components it can hold. This provides greater expansion potential. Bigger cases also provide better air flow which is essential for cooling. And large cases are easier to work with.
- The more compact the case, the less expansion potential it has; working on it is often much more difficult, and usually air flow is more restricted.
- Smaller cases that come with a power supply usually have lower wattage, reducing the number of internal devices that can be installed.
- The more features in a case design, like the power wattage or the number of bays, the higher the cost.
In any repair job that involves inspecting or replacing internal components, the technician has to open the case. This usually involves removing four screws at the back of the computer with a Phillips screwdriver and then removing the case's cover.
Note: The size of the heatsink and fan required to cool the Pentium 4 CPU can damage a CPU or destroy a motherboard when subjected to vibration or shock. To prevent this, the Pentium 4 chassis has four standoffs to support the heatsink retention brackets. These standoffs allow the chassis to support the weight of the heatsink instead of depending upon the motherboard as with older designs.