Not booting up - ram, PSU or gpu?

Hey guys, first post here

I have an AMD x2 3800 with a DFI Infinity NF4 Ultra mobo, 2x 512mb DDR2, and a 7600GT. However, it isn't booting up....I press the power button, and the fans spin up, the DVD light comes on, and the power button just keeps flashing. No POST, nothing appears on the monitor.

If I take out the gpu, and all but one RAM stick, I get a long beep which, according to the manual, indicates that a DRAM error has occurred - and the power light keeps flashing. If I then put the gpu back in, I get no beeps, nothing on the monitor, and the power light just flashes.

Any idea what the problem is? I've tried alternating between both ram sticks (when trying a single stick), and tried different ram sockets.

I've tried resetting the cmos by taking out the battery and unplugging it (after trying to reset it through the jumpers), and buying a new battery, but no luck.

 

Just tested the PSU while attached to the mobo. Tested the motherboard connector, all rails seem to be fine, though the 5v and 12v rails seem to spike to double their voltage for a moment when the PC is first turned on.

The only things attached were the ram, gpu, cpu, and fans.

 

Well it doesn't look like it's the gpu - just put it into a different PC

I can't test out the ram though - it seems to take a different type, these modules don't fit.
Hmm...any ideas?

Just put another PSU into this PC, and the problem remains.

So that indicates it's either RAM, or the motherboard....any idea how to figure out which?

Considering I have 2 sticks of ram, it'd be extremely unlikely it'd be the ram, wouldn't it?

 

Hi, the last time I had a similar problem the video card wasn't seated in tight enough even though it looked like it was and the monitor was black with no output. I removed it and cleaned the contacts and reseated it and it worked. Try reseating your video card and ram several times or try onboard video if your motherboard has it. I believe your 7600GT requires at least a 500 watt powersuply.