Computer shutdown on exitting

[LDiCesare]

I installed the demo and played 100 turns. Well, I had a lot of remarks and maybe maybe not in terms of buying, but then I clicked Exit and...
Computer shutdown.
This may happen in case of excessive heating, which happens with some games which are GPU-demanding, but for Civ, that looked weird. I checked and the computer wasn't particularly hot.
So I ran again, repeated, and same result: Exit means the computer gets shut down forcefully.
I won't buy the game if it has the effect of screwing the operating system and potentially damaging the hardware. Does anyone know if there's some kind of funky video or stuff that runs on game exit, possibly that would require the GPU to do something and cause it to overheat or cause the computer to think it's overheating?
Normally, I'd expect the code to do exit(0) at this stage and exit cleanly...

Has anyone got a similar issue, and is it only in the demo or can I expect it in the full game?

 

[The_J]

What are your system specs?

 

[LDiCesare]

ASUS G71G, intel core2 quad Q9000 2GHz
4Mb RAM
Still using vista SP2.
GPU is nVidia GeForce 9800M GS.
And fan is probably failing to work as well as it should considering it's a bit noisy.

I wonder whether there's supposed to be a splashscreen/something at the Exit of the demo that may not be in the full game and would cause the problem?

 

[The_J]

No, i guess we would know that.

Do you run the game on high graphics settings (well, looking at your system you could)?

 

[LDiCesare]

I tried changing the settings. I went into DirectX9 instead of10, which removes the Fow, and it seemed to be fine but the GPU is definitely overheating.

I guess I should try to dumb down all the graphics, which I don't care after all, and see if the temperature remains ok. If not, I'll have to see if I can find some hardware to cool the computer or fix the fan somehow to be more effective.