Computer won't turn on (lights blink once)

[steamroller16]

I accidentally hit the sleep button on my keyboard and now my computer won't turn on. Everything was working perfectly before I hit the button. Now when I press the power button, the lights come on for about 1 second then go off. About 3 seconds later, all the lights blink once and then nothing happens.

I have tried unplugging the power and plugging back in after a few hours. I have also removed all the components except the processor from the motherboard. So right now, the only connections to the board are the two power supply connections (24 pin and 8 pin) and the processor is in the socket.

Unfortunately, I don't have a spare power supply. Is there anything else I can try to narrow down the problem further? Any ideas why this might be happening?

Motherboard: Asus P6T Deluxe V2
Processor: Core i7 920 - 2.66GHz
PSU: Corsair TX 750W

Thanks.

 

[nikorr]

OK, i would start with BIOS.
Can u reset the BIOS?
Reset the CMOS memory the right way as is described in the motherboard manual using the clear CMOS link with the power cord unplugged.
How To Clear CMOS @ http://pcsupport.about.com/od/fixtheproblem/tp/clearcmos.htm
[flash=480,270]http://www.youtube.com/v/rdHH9KrceR0?version=3&feature=player_detailpage[/flash]

 

[mubin]

Yes, reset the bios first. I hope you will get rid of it if you follow the above method.

 

[steamroller16]

Just tried resetting the bios and the problem persists.

 

[nikorr]

OK, what about the RAM? What u got?

 

[steamroller16]

I have 3 sticks of 2GB each. I have tried with each one of the sticks one at a time and also with no RAM at all.

 

[nikorr]

Are they exactly the same model? Are they all the same?

 

[steamroller16]

Yes. They all came in a matched pack.

http://www.newegg.com/Product/Product.aspx?Item=N82E16820145222

 

[nikorr]

OK, can u try to boot with just 2 sticks?

 

[nikorr]

And u cannot get into the BIOS as well, right?

 

[steamroller16]

OK, can u try to boot with just 2 sticks?

Same problem. Tried all combinations of two sticks. I tried different slots too (I have 6 slots total).

And u cannot get into the BIOS as well, right?

Yeah. Can't get into the BIOS. Monitor doesn't even turn on.

 

[nikorr]

Check on the GPU, remove it, start the PC shut down and install it again and make sure the power for GPU is in and the GPU is locked in place proper.

And check if the fan will spin in it.

 

[steamroller16]

Just tried that. The GPU fan spins up, but only spins for as long as the motherboard lights are on (about 1 second). Motherboard behaves exactly the same with and without the GPU in the system.

 

[steamroller16]

Actually, now that you mention the GPU. I was playing a video game when I accidentally hit the sleep button that started all this. Not sure if it makes any difference.

 

[nikorr]

It all looks like the PSU is the culprit.

 

[nikorr]

Actually, now that you mention the GPU. I was playing a video game when I accidentally hit the sleep button that started all this. Not sure if it makes any difference.

Is it in the standby mode?

Is there a green light on mobo?

 

[steamroller16]

That's what I was thinking as well. Just wanted to cover all other angles before buying another one. Maybe I can borrow one from a friend to test.

I have another old computer that has a 20 pin power connector. Does it make sense to try my PSU on the old computer and see if it works? Would that help me determine if the PSU is bad?

 

[steamroller16]

Is it in the standby mode?

Is there a green light on mobo?

No. There's no green light. There are two buttons on the motherboard (power and reset) and they light up as soon as I plug the power supply into the wall but no other lights. I know these are on even when the computer is fully turned off. There is another light under the ASUS logo on the board which lights up when in standby and also when powered on and that light is definitely not on.

 

[nikorr]

It'll work, but the four extra pins were added to improve reliability of power delivered to the PCIe x16 slot(s).

So the GPU may not power up for more than a start.

 

[steamroller16]

When I said old, I meant really old. It has a AGP graphics port from back in the day. So I'll give that a try, but maybe not until tomorrow. I am using that computer right now.

Thanks for all your help.

 

[nikorr]

Good luck!

 

[sunney]

Soul go into your screensaver setting. Check your power options. If you have it set to Balanced or Power saving then it shuts down the hard drives after 30 minutes. After that it require just a click of the power button to wake it correctly. I usually set mine to High Performance to stop that. But you can change those settings in other options as well.
Making sure the hard drives dont turn off should stop this from happening and prevent the whole CMOS clear thing.

 

[steamroller16]

Just hooked up the power supply to that old computer and the power supply works perfectly! Now I am down to the processor and motherboard. Any suggestion on which one to try replacing first? I am going to have to buy new parts to try.

 

[steamroller16]

I tried something else that changed the problem. I removed the coin cell battery on the motherboard and put it back in after a minute. Now the motherboard stays on but it won't post and the display is blank.

 

[steamroller16]

Problem fixed.

Found out that a pin in the CPU socket was bent and carefully bent it back into place. Don't know how this happened since I haven't taken the CPU out of the socket for more than 2 years but I'm happy that it is all working again.