Since I know you're running Arma 3.... what's the cooling situation on this laptop? 9/10 times I run into this at work, the mobo has fried because of overheating to an extreme point. In my case, salesmen who close their laptops (they don't sleep) and they stuff em in a bag and travel. Sitting in their own thermal discharge is a death sentence for something like a laptop that doesn't have the cooling capabilities of it's desktop brethren. I would suggest taking it in as I don't see much other alternative (normally I scrap laptops that come in to my bench with fried mobos).
Good Luck.
