Graphics and Vista64 Ultimate Issues

Ok I just got myself a new pc,

2.4Gb Quad core
BFG 8800 Ultra
8GB OCZ DDR 800 ram
Vista64 Ultimate

Since I built it i have had nothing but problems, first off vista did not like 8gb of ram so I had to reduce it to 2gb just so I could install without it crashing then once installed I had to patch it to be able to use the full 8gb of ram. Once in windows the pc BSOD frequently with random errors from IRQL equal to Memory management errors.

After a few days of playing and increasing some of the voltages to components and installing a few patches i have got to a stage where it is a bit more stable and it just might allow me to run a game for an hour before finally crashing.

but now to the nuts and bolts of what this post is about

I recently bought 2 games, Crysis and Sims city societies. Installed them and patched them. I have all the latest drivers for my hardware. When I run the games and I have tried all the graphics settings from low to ultra. They all work but I am getting a Vortex / texture issue where graphics polygons are arching across the screen from an object into infinity. Its not the whole game and its playable for a few minutes until it finally crashes. Has anyone had these problems, could it be a graphics card hardware issue or maybe just that vista ultimate 64 is bad with games.

Any help would be greatly received.

Ive seen a similar problem in other OS's also. You could try to pull your video card and ram out then re-seat them. I've seen that happen with a Graphics card and just re-seating it fixed all the problems.
I'm not saying this is the 100% answer, but this has been the issue before.

Also the Video card could possible be defective. Have you ran your build on anything else besides Vista64 ?

Or have you tried running your build on just 2G of memory. Just changing the sticks out one by one or two by two and see if you have a bad stick.

What else you have in your PC? maybe the PSU is underpowered?

All your drivers updated to most recent?

With the BSOD, what are the stop errors you getting? (i.e. 0x0000007f)

You could always check event manager after it crashes...as far as I can remember, vista's is very extensive and has a hardware monitor as well, something may show up in there.

I see where you increased some voltages. Which ones? Is your RAM voltage set to mfg spec.? The OCZ I see at Newegg wants 2.1 v vdimm but most mobos will default to 1.8.

Perhaps try to get the system stable with 2 gigs of RAM only. If that works this would tend to point the finger at a memory issue.