maximizing/minimizing windows and games in slow motion

Hi,

I've had this problem for a while where occasionally when I boot up my laptop (Dell XPS), the windows would maximize and minimize in slow motion and all my games run in slow motion. A restart usually fixes the problem.

I've looked for solutions in the past but the problem always comes back. I was wondering if anyone can tell me what the problem is or how to fix it. I've tried chkdsk, hard drive scans, driver updates, dell diagnostic tool, pretty much everything that was suggested in other posts on this and many other forums regarding the same issue.

Thank you.