I had to send in my Acer Aspire 3 times within one year.
(bought it like 6 years ago) I hate Acer!

It constanly heated up, and blew my graphicscard.

Anyhow, try to open it, and clean the fans, to have better cooling.

I would also suggest to burn a Linux liveCD (Ubuntu or so) and try to boot it,
and see if the OS was the reason.