Constant reboot during gaming

sztazis

Honorable
Dec 12, 2013
2
0
10,510
I really can't put my finger on why it's happening.
I have an Acer Aspire 5750G (Core i5, 8GB RAM, Geforce GT540M, 120GB Kingston V300 SSD).

Recently, in the last month or so, I've been getting constant rebooting during gaming. Sometimes it takes half an hour, sometimes just 1 minute, but it's there, only the time varies. It never happened before.
I've tried Win7/Win8/Win8.1, fresh install everytime, only installed gfx driver and necessary directx, vcredist, etc.

I tried the latest stable and beta drivers, rolled back to 327.23, same old.

Mostly happens in Borderlands 2 and Grim Dawn (I've been trying to play these).
Sometimes it happened in-game, but a few times it happened during before I even got to the main menu.

Is there anything I could test/check/see? I've cleaned out the CPU cooler like 2 months ago. Should I maybe change the thermal grease on the CPU?
 
Okay, since I didn't get any error messages (just reboots all of a sudden), now I get the BSOD with nvlddmkm.sys.
I searched it up on forums, but they don't really post a solution to it.