Just a couple of weeks ago, my laptop started making a very loud roaring noise and experienced a severe slowdown in performance (programs and windows open very slowly) at the same time. It takes a couple minutes after booting up for the noise to begin, but once it starts it is continuous. At this point, I am thinking it is either one of the cooling fans or the hard drive. Is it possible that problems with the fans could cause a performance slowdown? But if it's the hard drive, is it possible for it to produce a constant roaring fanlike noise?