Of late I found my desktop PC crashing now and then. The situation was getting worse by the day and it was becoming frustrating to use the PC. I opened the box and got my fingers dirty, so before I looked further I decided to blow out all the dust with a vacuum cleaner. Loads of dust billowed out. I would recommend holding the CPU fan blades so that it does not spin uncontrollably. After the dust clean up, the PC is working great and no unwanted crashes. I guess the dust was preventing the cooling of the CPU.