I've had this pc for a few years now and everything has been fine. Recently i took a month or two off my pc and since i have returned I have found that my fps has dropped to about 120 fps (sometimes below 90) on csgo and 45-60 in rainbow six siege with everything on medium/high, I use to get around 250+. The temperatures seem okay so I am a little bit confused as to why this is happening. I have a GTX 960 with a i5-6400 processor. Any help would be much appreciated!