Next, check if the power supply has a switch at the rear if it is on (older models) and see if it works. Check for any foreign metal objects that may be stuck between the board and the case which is shorting it out, again the protection circuit would prevent power up to avoid damage to the various sensitive electronics. A faulty motherboard fan can also be causing the problem so check the fan if it works. You might have also forgotten to connect the power button to the board (along with the reset button) so check that too. A shorted reset switch can also keep the board in a state of permanent off, unplug it to see if that works.

Modern boards use plastic stand-offs to which the board simply snaps into place or is fastened to by ties. Older PC casings use brass ones that need paper or cardboard washers for the task. There may also be an issue with the alignment of the board itself (there was an issue with Gigabyte boards sometime back that had the whole board sagging in one place of the other which prevented the memory modules from seating properly. Thanks to answersthatwork.com for the details ) Use plastic tie-downs where a plastic tie is used to pull the board into alignment to solve this type of problems.

If there is still no activity, re-seat the memory modules and video card for they may not be properly seated and locked in place(some boards and cards have locking mechanisms that prevents them from unplugging themselves as the heat goes up when it is used due to thermal expansion). There are some motherboards that have issues with grounding; any contact with the casing (which is normally grounded to the earth prong of the power supply) would activate a circuit in the power supply that prevents it from working properly to avoid frying any sensitive equipment. Isolate the board by checking the stand-off and ensuring they are isolated from the casing.

If you have no way of getting proper grounding (which you should) insulate yourself from the floor by wearing shoes or stand on any insulating material such as a block of wood. Proper grounding prevents the circuitry of all electrical devices from frying in the event of failure and it carries away dangerous current from them sending them to the ground instead of through your body. Having grounding installed is not only necessary for safety but is common sense. Check out with an electrician so you can get your power source properly grounded to prevent injury to you and the other members of your family. SHOCKING!!!! Isn’t it.

Reminder: If you do know what I’m talking about don’t do anything and call an electrician to install grounding for your outlet (electricity kills). If there is grounding, then you might have a faulty power supple chord or one without the grounding prong (or it was removed). Power strips and AVR’s(Automatic Voltage Regulators) need grounding to work properly as well as GFI’s(Ground Fault Interrupters) for them to give optimal protection from shock. Tip: if you have a test light that’s normally used by electricians probe the outer chassis of your PC, if it lights it’s grounded and it can shock you.

Ideally, the power company provides this from the service entry as it enters the house and is distributed with the power cables throughout the house. Without proper grounding, all devices that consume electricity have the potential to shock and even kill if there was a pre-existing condition such as a heart attack. First, check if the house outlets have grounding with a multimeter if possible by connecting one probe into the powered side and the other into the ground side. If the house outlet is grounded it should read half the amount of total voltage you have in the house. For a 220 volt system, it should read anywhere from 100 to 110 volts.