Once the core components have been assembled onto the motherboard, it’s time to start prepping the actual build.
At this point, your build should be partially assembled on a table and consists of the motherboard, CPU pre-installed, cooler pre-installed (with CPU fan cable connected, and pump cables as necessary), and the RAM installed. If you installed the GPU and connected power to do a quick test that the components work, those devices can now be disconnected.
We’re going to transplant the motherboard with its memory, CPU, and cooler into the case.
Most mid-tower and full-tower computer cases have the same general layout. There are intake/exhaust positions in the front, top, and rear of the case (also useful for radiator mounting). Some fans may be pre-installed, and will have cables that need to be attached either to the motherboard or a fan hub (more on this in our cabling guide).
Most cases are also riddled with holes – passthroughs, they’re called – which are sometimes shielded with rubber grommets. These passthroughs offer easy routing for later cable management, and help to keep the system clean when assembled.
Drive cages tend to be located toward the front of the case and are largely meant for 3.5” HDDs. Many cases now have separated 2.5” SSD sleds for more prominent (or secluded) display of SSDs, e.g. behind the motherboard tray or atop the PSU shroud. 2.5” SSDs can be adapted to fit 3.5” hard drive slots, if the sleds do not already have mounting points (and most do). Some cases have modular drive cages, which means the unused pieces can be removed for improved airflow.
Before installing the motherboard inside the case, it’s a good idea to double-check our work on the earlier CPU cooler installation. Some tower coolers apply a good deal of force to the motherboard, particularly if over-tightened. Remember our rule? “Monkey tight, not gorilla tight.”
If a CPU cooler is too tightly installed, it will create enough stress on the board to cause a slight bowing. Ensure that the board is flat. If it isn’t, back-off some tension on the screws. If that’s still no good, validate that the backplate was installed facing the correct direction.
How to move the build inside the case
- Remove both side panels – they’re both coming off, anyway. Rest the case on its side to expose the main compartment.
- Ensure that the stand-offs are installed in the case. More below.
- Ground yourself.
- Install the I/O shield for the motherboard.
- Lift the board gently from the underside, ensuring that the CPU cooler (if a heavy tower cooler) does not awkwardly weight or warp the board. Do not lift by the CPU cooler. More below.
- Carefully line the board up with the standoffs relevant to the motherboard’s form factor – this is easiest to do by lining-up the rear I/O with the I/O shield, then the rest of the board will follow.
- Add a screw to each standoff position, securing the board. Start with opposing corners.
Why should you use motherboard standoffs?
Motherboard standoffs provide an electrically-safe spacer between the motherboard and the case. This is important, as case paneling is often made of steel and would cause a direct short (short circuit) if the motherboard were to make contact with the case. Although such a short may not cause any permanent damage to an intelligent motherboard and PSU, it will minimally prevent boot. Best to be safe and just do it right from the get-go, though.
Motherboard standoffs are brass spacers that use a hex driver to install. They can also be tightened by thumb and finger, though the screws that socket into the standoffs may later spin freely if ever removed. Your case may have markings for which screw holes / standoff locations are suitable for the motherboard’s form factor. If not, check the manual. An alternative would be to line-up the board against the case, then determine by eye where the standoffs belong.
Why should you use an I/O Shield?
The I/O shield is, simply, a metal cover for the rear I/O on the motherboard. There is minimal functional purpose. For the most part, it prevents stray fingers or USB devices from exploring inside the case. It’s worth installing the I/O shield just to ensure no one accidentally reaches too far in and touches an active component. This must be installed before the motherboard is mounted. – Steve Burke, GamersNexus