Blue Pixels /BSOD

[TRex]

Wondering if I could pick a techie's brains -

I have an intel e8400 cpu (socket775)running at 3ghz (standard ) with an asus 8800gt 500mb graphics card ,4gb ram , on a gigabyte GA-EP45-DS3R mobo with 500w antec psu. Windows Vista .

It's done me great for most games, and the main reason I could go back to playing ps again.

Howether ,2 days ago , I started to get random blue pixels all over my screen. I could hover my mouse over them and they would disapear , but moving the mouse would leave a trail of blue pixels behind it . I restarted the pc .

Upon restarting , I immediately noticed that on the login screen where I input my password to launch windows , all the colours were grainy and pixellated . I logged in, then the pc crashed with a diagonal pattern of pixels across the screen.

I restarted the pc manually in safe mode , and the error screen notified me it was display drivers that were causing it. I uninstalled the graphics drivers , and replaced them ( just to note that windows update had occured a day or 2 before this all started) . Restarted the pc as instructed , and I get BSOD.

I then reformatted my hard drive , reinstalled vista , did a full update on windows , put norton back on it and run a full system scan . Updated my mobo drivers and BIOS. After all this I went to official Nvidea site and downloaded a fresh copy of drivers , scanned the copy for virus then reinstalled them . Upon restart I get BSOD again. I restarted in safe mode , removed the drivers , and went to microsoft site , they had 8800gt drivers there , downloaded them , scanned them and reinstalled them . Same thing BSOD. I unistalled them , restarted the pc and the pc runs 'normal' albeit with no graphics card (or at least no drivers) .

I can access the internet , hence why I'm posting here. But I do notice that if I'm on a dark background I occasionally can see some slight plue pixellation on that background. I've checked my pc, the fan is running fine on the graphics card , and my system temp is 28-31 degrees .

I can only conclude that the 8800GT is knackered ? Hope someone could clarify this . I really didn't want to spend any money right now ( partly because I'm a little strapped after paying for my son's school ski holiday , and also was waiting until ps:n was a bit closer ) but if it really is the case, what would be a comparable upgrade to replace faulty card with or any advice .

Thanks.