PC refuse to turn on.


Dec 17, 2010

A year or so ago I've build myself a PC, it's also the first time I've build a PC and been working fine until one day it won't turn on any more.

I've tried to find out what's the problem by asking computer repair shop etc. and apparently it's a faulty Motherboard, so I return it and got a new one, and I've also got a CPU replacement as there seems to be a bent pin.

After I got my new CPU and Motherboard, I reassemble them back into my case, and the same problem persist.

It should be note that my testing procedure is just:
1. turning the PC on and off.
2. unplugging the power cable put it back into the power supply and then turning the PC on and off.

When I tried the 2nd testing method, the PC fan would turn for 1/2 a second and then the PC would die again. and when I try turning on and off again, nothing would happen, I would have to unplug the power cable, re-plug it in, then turn it on for the Fan to spin for 1/2 a second.

Also during the testing session, I've did manage to turn the pc on once and it actually boot. However when I turn the pc off and try to turn it on again, the same problem occurs.

I've been searching the web to look for similar situation and look at their solutions and a few people seems to have the same problem as me, and the answer they get are either a faulty power supply or Motherboard.

At first I thought it was a problem with the power supply as the Motherboard is showing green light when the power supply is turn on. And I thought to myself "there's power in the Motherboard, so it can't be it".

Then I tried this: http://www.youtube.com/watch?v=5FWXgQSokF4

and the fan actually works, and so does the lighting for my case.

Now guys, I would really appreciate your guidance.

Could the motherboard still be faulty even though it's showing green light and look as if it's powered?

Could the power supply still be faulty, despite being able to power the fan, as the fan only consumes fairly little power?

Ultimately my problem is still not being able to boot my PC, hence it may be none of the problem with the Motherboard nor Power Supply.

Extra Info:
My motherboard: Asus M4A89GTD Pro AMD 890GX Socket AM3 / AM2+ DDR3 Motherboard
My Power Supply: Antec TruePower New 650W Modular PSU - 80plus Bronze and SLI Certified 3x SATA
My CPU: AMD Phenom II X4 955 Black Edition Socket AM3 3.2 GHz 8MB L3 Cache

For any other extra information, please ask.

Thanks in advance for your help, I appreciate it.
Ok inside your case there should be some min colored white and another color cables, make sure you look in your motherboard manual and make sure everything, EVERYTHING is plugged in good