Question : Problem: GeForce 8600 GTS losing video?

Hi all,
(Sorry for the lame point offering... I haven't used EE much lately and am awaiting a refund.)

I just bought an HP m8407c (it was cheap), then bought a couple small upgrades.
First off, the system is an Intel Quad Q6600 w/ Vista 64.
It came w/ a single Asus GeForce 8500 GT (it's not SLI) and I got a PNY 8600 GTS 256mb to put in instead.. not a big deal.
At the same time, I upgraded the PSU to a 500w OCZ StealthXStream (two 12v rails at 18a per), and put in a couple new nVidia DIMMs that came w/ the 8600GTS (i figured they'd be better than the memory in the PC.)
Booted up and everything's fine... Installed the drivers for the 8600, ran some windows update junk, etc.

Then, it started happening -- seemingly at random -- that video would go black, fans kick on and I have to power off. Then I noticed a couple specific times it happened:
- When I tried the Windows system rating thing -- and I assume when it's probing the video
- When I previewed a screen saver (the one w/ bubbles or something)

Note, I haven't done any gaming on here. I haven't monitored temperatures yet or anything.

Anyone have any ideas?

Answer : Problem: GeForce 8600 GTS losing video?

Nvidia drivers are typically better than Vendor-supplied if only because they are more up to date.

Personally it sounds hardware, if it was driver you would be getting BSOD.