Weird graphics glitches on my laptop?

Okay, I've got a Dell 1520 Inspiron (2.2gig dual core/2gig of ram/8600M GT) for Christmas and for the last week or so I've got weird as hell graphics glitches occuring on high-intensity games (Crysis/Call of Duty/Source engine stuff). It's hard to explain but I'd best describe it as textures which like, stretch off into the distance from random points. There's no discernable pattern to the glitches, and I've so far surmised that:

1. It's not overheating (running at a cool 50c)
2. It's almost certainly not the drivers (Dell Defaults/2 kinds from laptopvideo2go)
3. It's not the settings (tried minimum settings, plus it's across all heavy-load games.)
4. It's not something I've installed, I think (tried system restore, didn't help.)
the cards not OC'd, and Dell support sucks balls and couldn't help. Is my card fooked? Do I need to get my laptop replaced? Could it be anything other than the card, e.g. the RAM?
Feel free to suggest getting it replaced - it's still on warranty.

Example picture of problem (it's sometimes much worse, covering entire screen):
http://img222.imageshack.us/img222/9023/graphicccssta0.jpg

1. The CPU or the Graphic PU? It looks like overheating.

Ah. The CPU was the circa 50degrees.

I just ran a fan control program whilst I ran 3DMark06, and, with me forcing the fans to run max throughout the test, the CPU temp peaked at 78degrees C (!?) and the GPU peaked at 54degrees. Interestingly, or perhaps inexplicably, there were none of those 'glitches' during the first or fourth graphics test, nor in either of the CPU only tests. they *only* occured during the second and third graphics tests (and in the third one, they only appeared on the boat...)
So, is that CPU temperature unusually hot?

Ammendum: in the post above, I meant to say 'Ah. The GPU was the circa 50degrees.'

Idiot.

Doesn't look like a heat problem to me from the picture.

>it's sometimes much worse, covering entire screen
Well then post one of those though.