Game causes windows to shut down

I haven't been able to play for longer than 30 minutes, because without warning while playing my computer shuts off.
No warning, blue screen or anything.
And it only happens with this game; I can play WoW and League of Legends for hours with no problems.
The only thing I've done to remedy this is disable the auto shut off that happens when my computer gets too hot. This didn't fix it, and PoE doesn't make my computer uber hot (as opposed to WoW on full settings)
Anyone else have this problem? Or at least know a fix?

Seems a there are quite a few ppl with this same problem, (inc. myself)

People talking about it in this thread, but no answers or mod response yet.

http://www.pathofexile.com/forum/view-thread/68140