Laptop constantly crashing.

So for the past month or so, after playing GW or running more programs than usual for about 20min my laptop crashes. I've been playing GW on it for more than a year, and it recently started crashing all the time after I installed Hellgate:London on it which I have uninstalled thinking that may have been the problem, but it still constantly crashes. I've also tried various virus programs, defraging, ect..and still crashes. Any advice/ideas?

Could be a heat issue.

Specs?

Might want to install some heat monitoring software, i use Notebook Hardware Control which is perfect. Also use your laptop on a hard surface if it isn't already, like putting it on your lap or on top of a pillow will make it heat up like crazy.