Computer Shuts Down Suddenly in Some Games

[Grozzy]

I've had this computer for quite a few years now, with no problems like this.
It's a IBM T42 Laptop

So, the problem: When I play a game, it shuts down, no warning at all, I guess it can happen like between 45-75 minutes into the game I'm playing. I've checked if it's something with the power, it wasn't.
So far it has shut down in Scarface: The World is Yours and Gangland. But in any Steam game, it doesn't do that, I've tested both Day of Defeat and The Movies.
So I also checked if it had something to do with the CD, since both Scarface and Gangland were run from a CD.
So I downloaded a crack for Gangland (yeah, sue me) but still the same.

I kind of tested for overheating too, I let it be ventilated and stuff like that, didn't put it on any cloth, in fact, where the fan is wasn't standing on anything, but still the same.

But why does it then happen in older less requiring games? If it's overheating that is

...

Just copied my question from Yahoo Answers to here, because I've posted it there 3 times, no help. Was hoping you could help me?

 

[Prometheus]

I think it's overheating. Posssibly because of the way the old games work.

Try adding a method of cooling.

 

[Grozzy]

I guess it could be overheating then.
But I've had this laptop for quite a few years now, and it only started a few days ago :L
I guess it's time for a new pc soon :L

EDIT: Found out it also does this on Oblivion, but still not on any Steam games. Team Fortress 2 is even newer than Oblivion, same about Portal, but they both work perfect.

 

[DDRtists]

Your RAM may be getting old or corrupted. Perhaps run some RAM checks to make sure they're still running as they're meant to be, as the one time my older computer was randomly restarting like you said yours does, it turned out it was the RAM when I too thought it was overheating.

 

[Grozzy]

Tried something about the RAM stuff you mentioned, downloaded a thing that clears up your RAM every time it drops. (I think)
I also just randomly tried adding Oblivion as a non-steam game on Steam, guess what, didn't crash.

So I don't know which of those fixed it.

 

[Prometheus]

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