Ok bear with me a moment. I just upgraded my pc. I bought these new parts:
ASUS PN5-E SLI
2 GB OCZ Platinum Rev 2 DDR2-800
WD2500KS 250GB 16mb cache SATA drive
I reused my:
480W Antec Neopower
Lian Li PC-7 B plus
Sony NEC Optiarc CRX320EE-BS DVD 16x
EVGA 7900 GT
I am planning on replacing the 7900GT with a 8800GT. Anyway I built the PC using the 7900GT. The PC booted fine and I was able to install Vista fine. I installed drivers/software and everything appeared to be working. I did a mild OC to 3200mhz on the CPU going 1600 on the FSB and leaving the memory alone. I am able to play games such as COD4 on it. What's strange is that I happened to look in the case and noticed I had forgotten to plug up the external 4 pin power cable to the 7900GT!! When I tried to plug the power cable (after shutting down of course), I restarted the PC and the screen was all fuzzy and static-filled like it was overheating. I shutdown the PC using the power button then removed the 4 pin power cable. Everything works fine again. Why don't I need that power cable anymore? I did set the PCI-E to PCIv2.0 in the Bios. Anyone have a clue?
Heh, so what were you plugging into the 6-pin slot? Probably not the CPU cable since you're obviously able to get to desktop. Did you put the extra +4pin from the ATX connector in there? I bet that would give some funky results if it even fit.
I am writing this from work and from memory, so I must have my connectors wrong. I thought it was a 4 pin but it must be a 6. Anyway I am sure I plugged the correct power connector to it whatever the pinout is. The Neopower is a modular power supply so the only cables on it were the ones I had before. No extraneous cords to be confused and it plugged up easy without forcing so I am 95% sure it was the correct power cord.
Ah, that happens. When I first bought my M2N board, I accidentally called it a P5N board. (Doh!) Maybe the new motherboard is providing sufficient power even without the extra 6 pin connected. It's the only thing I can really thing of.
*Edit* Every time I see this thread while browsing around, I start to sing the Ghost Busters theme song in my head...