HELP PC won't POST, possible causes?

[BUBrave]

Hey all,

I built a new PC from scratch with all new parts just over one month ago. While just browsing the internet today, my computer suddenly shut off. I tried a few times to start it up and it would just shut off all power immediately. After giving it some time, I could get it to power up, but it will not POST (I see nothing on the monitor). My MOBO has an LED read out of "FF" which corresponds to "Power on and first initialize CPU." After calling tech support, I reset my CMOS several times and tried booting with only one stick of RAM. At one point the board read "D1" which I believe is RAM related.

Can anyone tell me if this sounds like a RAM problem? The only other unusual thing is that three red LEDs are lit on my HD4890, which correspond to errors according to tech support. Is the Video Card the problem?

This is my first PC build so I am not great with hardware, someone please help give me suggestions.....

Specs:
MSI 790FX-GD70
PII X3 720
Corsair TX750W PSU
4 GB Corsair 1333 DDR3
WD Caviar Black 640GB
Sapphire HD4890 1 GB

P.S. I have not overclocked in any shape or form.

Thanks in advance!

 

[shortstuff_mt]

The three red lights on your GPU would indicate a power problem. Did you check to make sure that neither of the 6-pin power connectors has come loose on the GPU?

I would go through the checklist in the "READ before posting about boot problems!" sticky. If nothing in the checklist works, it's possible that the PSU has gone bad. Corsair PSU's are very high quality, but no manufacturer has a 0% fail rate.

Did you also check each stick of RAM by itself in every RAM slot? I know you said you tried with one stick, but maybe that was the faulty one.

I wouldn't be surprised if the motherboard is to fault, either. I haven't had good luck with MSI at all.