Any known vista 64 ultimate issues?

[JetEskimo]

Getting a bit of a run around from Gateway (go figure), trying to pass the buck over to you guys for the crash issues I am having in game. After a brief amount of playtime, the machine just shuts down on a dime (no warning, errors, or game glitch). First time happens fairly quickly (with a half hour or so), then more frequently has I reboot/reconnect. I've done this dance on a few different occasions, and it will shut down as quickly as within a couple of minutes by the third time.

Using a new Gateway P173X-FX

OS: Vista 64-bit Ultimate
Processor: Intel Core2 Duo T7500 @2.20 Ghz
Memory: 4gb
Video: NVidia GeForce 8800M GTS 512MB


Reeks of an overheating video card to me, but thought I'd see if you had any advice.

Thanks.