computer won't POST

[Gusty987]

I have a computer that as of this morning refuses to POST. All fans power up normally, but there is absolutely no video signal at any time.

This morning the computer was recycling itself constantly, powering up to the POST screen, quickly shutting itself off, restarting, showing POST screen, restarting, etc. I figured it was maybe overheating so I opened it up and cleared the dust (a lot) out of the heatsink fins and elsewhere.

After that, it began not POSTing at all, never showing anything but black screen on the monitor.

I have tried swapping out RAM sticks, using the build-in video output, and reseating the CPU. Then I decided to take everything out of the case, and set it up in a bench-test format, with just CPU, memory, and video card connected. Nothing.

At this point, I don't know whether to suspect the motherboard or the power supply. I'm leaning towards the power supply since it is about 8 years old. Any one have any ideas though, before I start by replacing the PSU?

Specs:

Gigabyte G41M-ES2L mATX
C2D E4300
eVGA 7900GS
2x1gb G-Skill DDR2
380w Antec PSU

 

[Paperlantern]

That would honestly be where I would go first too. PSU.

 

[Frosty192]

Is the computer giving you any POST beep codes? If your case has no speaker, you could try a speaker from another case. I had a similar problem recently and after looking up what the beep code meant, I found I had to re-seat the video card.

 

[mfenn]

Yeah, I'd suspect the PSU as well. You can also check for bulging or leaking caps on the motherboard, but I doubt that's the problem given that it is relatively new.

 

[Gusty987]

Not getting any beeps, and the caps on the mobo look okay, so I guess I'll look into a new PSU...