So, I upgraded my desktop a few months ago in order to be able to play video games my old PC couldn't handle. It was all going good I could play max settings on big games with little to no lag. But about a week ago my rig just seemed to die a little. Games that I was able to play without any lag (such as The Witcher 3, just cause 3, ect...) started to lag to the extent I was unable to play them properly (even with the graphics lowered). I'm not sure whats going on but I know its not because my rig is full of dust and dirt (I keep it clean) and I just did a full factory reset the other day so its not do to programs I have downloaded.( I also shut it down at night so it is not running at all when I am not using it.) I'm looking for any possible reason why this is happening and solutions to fix it.