I have this problem w/ my HD, both my new 45gig 75GXP, and my old maxtor 13gig (3x 4.3gig platters). Say i surf the net or have my computer running simple things that don't require heavy HD trashing (IE loaded into memory already), and I suddenly open up something like MS Word, my whole PC lags for a few seconds. Winamp will replay the same second of music over and over for a few seconds, and the pc will just lag. I'm not sure if this happens if I am already using the HD for something, but the lag is quite annoying. Anyone have a solution or explaination for this? Thanks!