STEP 1: Clean computer inside of dust
STEP 2: Take out memory modules and clean contacts and reseat them - try again - if not working go to step3
STEP 3: Take out the video card ( if does have one ) and try on board ( if does have one ) - if not working go to step 4
STEP 4: Take out ANY other addon cards like modem, tv tunner etc and try again
STEP5: Can also disconnect PS plug ( 24 pins ) from mainboard and try shorting GREEN with any BLACK using a paper clip or a wire - PSU should turn ON - this will pretty much tell you if the PSU is OK
STEP 6: You can disconnect Front pannel connector on mainboard and try shorting the pins for the power button - this will tell you the power button is causing the fault or not.
Other than this if it's still not going than you might have a faulty mainboard
Cheers and good luck
Edited by Sophia77, 25 December 2012 - 01:52 AM.