Sudden Drop In Performance By Around 60% / Most Noticeable In Games

when I downloaded the Torchlight 2 demo from Steam and started playing it on max settings. Lo and behold, I only got 13fps while playing the game Which is weird because I'm able to hit ~25fps playing Crysis 2 on max (a game with much higher sysytem requirements) After more observation since then, I've noticed that my laptop in general has slowed down a bit the mouse movement isn't as smooth, apps don't load as fast, and the system in general doesn't respond as quick as before.So finally, I decided to benchmark my system again running Crysis 2 on max. Luckily, I bench-marked it two weeks ago using Fraps and got this result on max settings: Ultra Detail; DX11; High-Res Textures Min, Max, Avg 16, 31, 22.398..But just now when I bench-marked the game again - at the exact same part of the game I played.That's a 60% drop in FPS, which makes me positive that there's something wrong with my laptop but I have no idea where to start diagnosing this problem My system specs are in my profile.