GIGABYTE Extreme not posting

[Badbonji]

Just installed a new graphics card, a HIS HD5970.

The computer booted into windows fine, cleared out the old drivers and rebooted.
It got half way through the RAID BIOS when the video signal just dropped out and it hung.

Now whenever I start the PC I get an error code 88 (8B I think it is supposed to be.)

Why has the motherboard suddenly stopped working? Tried with 1 stick of RAM and my server's HD5450 in two different PCI-e slots but no dice, the error always appears as soon as I turn on the PC.

I bought this motherboard in December 2008, does that mean it is still in warranty?

[Dark Mantis]

Yes your warranty is still valid. It is guarranteed by Gigabyte for 3 years. What PSU have you got and is it still running?

[Badbonji]

Seventeam 1000W PSU, I assume it is working still as it still switches on, had no stability problems with the GTX295 just before!
Just so weird how it would fail so fast!

[Dark Mantis]

Try the old short the green and black wire trick to test if it is indeed working ok. At least that will prove it. The power supply is big enough but that card is a bit of a power hog and if the PSU was wobbly it could have put it over the top. Another thought is to try clearing the CMOS and loading the BIOS optimised defaults. Then make sure all of the old graphics drivers are gone.

[Peteruk]

Seventeam 1000W PSU, I assume it is working still as it still switches on, had no stability problems with the GTX295 just before!
Just so weird how it would fail so fast!

Well have you tried that 1000W PSU in another computer like your server just to be sure?

[Badbonji]

Yeah the PSU is fine! I tried again this morning and it managed to POST and I entered the BIOS as I cleared the CMOS, but then it froze and will not POST anymore, but it doesn't provide an error code and just keeps cycling on/off.

[Dark Mantis]

Do you have a buzzer installed? If so does it not make any sound?

[Badbonji]

No I don't have a speaker 

[Dark Mantis]

I would recommend installing one then as they are very usefull when you have problems like this. I know that you have the display but the buzzer works better sometimes.

[Badbonji]

Hmm, video occassionally works but most of the time it just cycles on/off. Not sure what the problem is here, but I am thinking it is a motherboard problem. I cannot try another CPU, but have tried another GPU and different RAM.

[Dark Mantis]

I does sound like the motherboard is on the way out. The only other thing is to check each individual connection to the motherboard from the PSU. Make sure there are no loose connnections etc.