Not being funny, but when was the last time you had the case open and cleaned it? I only mention it as a mate at works PC was running awful - fans always on and it was maxed out and kept crashing. He brought it in and I opened it up and the CPU heatsink was SOLID with dust n fluff n shit Cleaned all inside of PC out, and he says it has run sweet as since then - no crashing, no freezing, and he never hears the fans go into overdrive lol....