how to determine if bad motherboard, or cpu
Well you can look for blown capacitors on your motherboard, but the easiest thing to try is to test your components in a nother setup to make sure they work one by one. It could just be your video card.
Do you hear your computer POST, or beep? If so, it might be your vid card. You can also unplug everything and try a bare bones boot with just your mobo, cpu, ram, and vid card. This will should narrow it down, becaue if it's your HDD or something then it will still boot and allow you to get into the BIOS. But if it still doesn't work it is a problem with one of those components. Test accordingly in a different system if available.
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