Computer won't turn on

[dredd2929]

My computer was working just fine and one day is just wouldn't turn on. I hadn't installed anything or connected anything new. I opened up the case and checked all the connections. All the cards are seated properly. The motherboard power light is on (ASUS A8N SLI Deluxe). I checked to see if the power supply (PC Power and Cooling Turbo Cool 510 SLI) was working by shorting the ground and power on pins on the ATX motherboard connector and it worked just fine. I've narrowed it down to the power switch or the motherboard. Does the power switch just short the two pins on the motherboard that it connects to? Can I short them directly to see if the problem is with the switch or the motherboard?

 

[mpilchfamily]

yes shorting the power pins will turn the system on. If that works then the case switch is bad if not then the motherboard or the PSU may be bad.

Now just because the PSU starts up when you short teh green and a black wire doesn't mean there isn't a PSU problem. You need to start it up with several items connected to it and use a DMM to check the voltages.

 

[dredd2929]

I tested the PSU (shorted the green and black wire) with everything still connected (except for the ATX motherboard connector of course). I put a hard drive jumper on the two power switch pins, and the computer wouldn't turn on (I used the switch on the power supply). Does that mean the motherboard is shot?

 

[mpilchfamily]

Ok your jumbled in your exsplanation. When you shorted the green and black wire did everything turn on?

Sounds like you also shorted the motherboard pins but nothing turned on.

If the PSU powered up but the motherboard didn't then the motherboard is the porblem. Get another one.

 

[dredd2929]

How, for the love of Pete, can I short the green and black wires on the ATX connector with it still plugged in? It has to be unplugged, and therefore, everything cannot turn on when the PSU turns on. However, the PSU was still plugged into everything else, namely the optical drives, hard drive, and fans.

I actually was able to narrow it down to the motherboard and have since replaced it. Everything works fine now.

Thanks for trying to help though.

 

[SergeC]

If you short the pins on the motherboard that the power switch connects to, it turns on the computer. I'm pretty sure that's what he was saying.

gj figuring it out!

 

[dredd2929]

OK, I celebrated too early.

I went to turn on my PC today, and again, nothing. The eerie thing about this is that it will be working just fine and then out of nowhere it won't turn on. The last time I used the PC was Saturday and as I said, no problems. The motherboard is brand new (ASUS P5Q), which is what I identified the problem to be last time this happened (last MOBO was ASUS A8N SLI Deluxe)...but maybe that wasn't the problem??

Any ideas?

 

[HOOfan 1]

Here is a link for some troubleshooting help