I may be tottally wrong here as I am no where close to being an expert on these matters but my wife's comp was getting really sluggish. It was slow from start up to shut down and we ran every kind of program we could think of to find errors. The harddrive did have a few bad sectors but we eventually found out that one of the RAM chips had crapped out and once we replaced it everything was fine(Except for those bad sectors) and back to normal as far as the speed was concerned.