Suddenly, my computer hates touhou (and still does!)

[Fossil Goo]

So I've had this laptop for a while, and had Subterranean Animism for a while. And throughout that whole while, it's always run perfectly, without any issues.

But suddenly, now whenever I run Subterranean Animism (and Team Fortress 2, for that matter.....) it runs for about ten minutes, and then my computer instantly shuts down. Not even a screen or anything, the power just suddenly cuts off. I know it's not overheating, because it's hardly lukewarm when it happens and I've tried using a cooling pad, but to no avail. I've also tried updating my video driver, but that apparently didn't solve anything either, though it's possible I did that wrong because I'm not sure I totally understood it. Any ideas as to what the issue is?

[chirpy13]

I've... Never heard of anything like that.  But just to confirm, is it plugged in?  I know my laptop's battery likes to die pretty quickly now.

That or check for malware I guess, that seems like the most likely cause to me.

[Agent of the BSoD]

Did you have any updates to your video driver before this happened? Sometimes, newer drivers can cause problems for whatever reason. If so, maybe downgrade back to a previous version and see if that solves anything.

Also, does this happen to any other games on your computer? Maybe try experimenting with some miscellaneous games and see if they do the same thing. (basically just to know if Touhou 11 and Team Fortress 2 are the only ones or not)

[Momiji]

The power supply might also be dieing (not enough wattage/voltage) or dead, and the battery's drained like chirpy suggested.

[Fossil Goo]

Well, it's been plugged in every time it's happened and apart from suiciding whenever I run touhou or team fortress 2, it runs perfectly fine. The battery life is quite good too.

The video driver update thing seems most likely, since my laptop tends to install automatic updates fairly regularly. I dunno what all it installs, but a video driver thing seems like it could be among it.

....so how do I downgrade my video driver? :V

[DX7.EP]

One solution is to go to Device Manager -> Display Adapters, right-click the video driver listed, and select "Uninstall" (on XP, IIRC it is the same for Vista/7).
Then go to your graphics card/chip vendor's site and download the previous version of the needed driver, and install that.

I never had this issue with video drivers (even crappy ones such as Intel's), so I'd blame malware, DirectX (since Touhou and TF2, among many Windows games, rely on it), or Windows Update (its driver downloads are questionable at times - I'd just go to the manufacturer's or OEM's site for them).
If all else fails, a format and clean install are the best way to go to clean out all that bloatware by brute force.

[Fossil Goo]

Uninstalling my video driver and reinstalling it (the site didn't seem to have older ones) fixed it! It also caused my antivirus to pick up some malware and delete it. I haven't tried touhou yet, but I just played an hour and a half of TF2 and there seem to be no problems. 

EDIT: OR FUCKING NOT. Turns out apparently TF2 only works in offline mode, touhou still kills it, and now of all things freaking MAPLESTORY kills it. I've found and removed some malware and reinstalled my video driver, and there seem to be no problems with DirectX. Any other ideas?