Troubleshooting for Cases and Power Supplies

The most important part of a computer case is its power supply. Unfortunately, it's also the part that has most of the problems for a case. There are two situations when a new power supply may appear dead on arrival (DOA) when they are actually working as described below:

Most cases and power supplies these days are made and tested in China and other Asian countries where 220V electricity is used. Desktop computer power supplies do not switch the power voltage automatically. (Most notebook computers do!) If the factory forgets to turn the manual switch back to 110V for the North American market after testing, the power supply would appear DEAD if you use on a 110V-outlet. Therefore, always check the voltage setting on the back of a new power supply FIRST if it appears dead.

Do not expect an ATX power supply to work by simply plugging the power and turning on the switch. ATX power supplies are soft-switched on and off by the motherboard and BIOS. Therefore, you must plug it to a working motherboard with a working microprocessor, memory and video card to work. If your computer does not turn on after you turn on the power switch, it may not necessarily mean a dead power supply. The problem might be with the motherboard, microprocessor, memory or video card instead. You must examine all these components to isolate the problem.

The most effective technique to tell if a power supply is causing any problem is to use a different one to see if it solves the problem. If everything works with a different power supply, then the new power supply is most likely the troublemaker. Alternatively, you can plug the new power supply to an existing, working computer to see if it works there.

Computer cases are highly modular. If your computer case is still under warranty, you don't have to send the entire case back if only one part of it is defective. For instance, send only the power supply back for exchange if only power supply is dead. The same is true for the face panel and cover. This would save you quite a bit of shipping and sometimes downtime.

More than 70% of all computer problems are related to cabling and connections. Ensure that you all the power plugs are connected firmly, including power connections to your motherboard and all the drives.

Make sure the cooling fan inside the power supply is working all the time. Reach out to feel the fan behind your case often. Clean the fan if necessary. If your case feels warmer than room temperature, check the power supply fan first. Most power supply fans are difficult to replace. You are better off to replace the entire power supply since the new one comes with a brand-new warranty.

Before ATX form factor became popular, the compatibility between a power supply and a specific motherboard could be problematic. However, this problem nowadays does not happen very often any more.

The rest of a case is mostly mechanical. You should be able to find a way to get around most of the problems if you are mechanically inclined.