Motherboard failure or Power supply failure?

[skchoe]

Dear all.
Yesterday, I did big trouble. My machine didn't respond any when power is on.
Asus M3A78-EM, AMD X2 4680e, Antec True Power 2 430W.

What happened was that I have another old computer that is not on any.
AMD 64 2300+, Asus K8 xx board w/ 754 chipset.
I wanted know if only power supply is broken. To test it, I connect above power supply to
this old mother board. No luck. So I wonder if old power supply is working. I use the old power
to new mother board, No luck.

After that my original computer doesn't turn on. Today, I borrowed a power supply and connect
to my mother board. CPU/case fan started to run only for 2 sec. No luck. The borrowed PS is
just 300W made by Dell.

Specially for computer part, it is hard to buy online without assuring it works.
What would be good way to fix it?

Thanks in advance.

s.

 

[dr.stevil]

same thing happened on 3 AMD64 based systems of friends/family in last past year. Nothing I did could get any of them working, tried swapping PSU's, processors, memory and nothing worked. I assumed it was just some really bad luck.

not saying it's the same thing, but it sure sounds like it

 

[gigaxtreme1]

Follow complete troubleshooting procedure. Remove motherboard from case and try to start on an insulated mat with only the motherboard, vid card and one stick of ram

 

[skchoe]

My observation when I plugged in other power supply was that the fan on cpu and case run 2 second and turned off again. Can this be a clue for motherboard is healthy?
I wish the reason why it was turned off again is the lack of power to run my video card(nvidia 8600GTS) and cpu.

Any idea?

 

[imajeanius]

Follow complete troubleshooting procedure. Remove motherboard from case and try to start on an insulated mat with only the motherboard, vid card and one stick of ram

that's what i'd do. pull everything out and hook up just the bare min. pick 1 item (power supply or CPU or memory) and swap out with all possible combinations (that you have available to you) and then move on to the next component.

 

[TeeJay]

Follow complete troubleshooting procedure. Remove motherboard from case and try to start on an insulated mat with only the motherboard, vid card and one stick of ram

+1

You'll easily figure it out that way. If you can also borrow someones motherboard that'd be compatible with your stuff would help too...

Tj

 

[Pepsiennis]

Follow complete troubleshooting procedure. Remove motherboard from case and try to start on an insulated mat with only the motherboard, vid card and one stick of ram

It sounds as if something within the case is shorting out the motherboard. As Giga... advised, remove the motherboard, use only the basic extras to get a boot: Video card, one stick of ram in the slot nearest the CPU (not electrically optimal, but what all MB vendors advise), and keyboard.

If it works out of the case with only these bare items, then it is something in the case causing your troubles. Clean the case of lint and foreign matter (dust bunnies). If it still doesn't work, then reseat the ram as carefully as you can.

Just remember, a short can damage any component along the connection, from PSU to GPU to Hard drive. But the most common issue is the motherboard. So take it back and get it replaced.