My Powerbook hard drive recently bit the dust so I decided to upgrade to 7200 rpms. The instillation process was nerve racking but I had a few things go wrong. You can read about that here. Drive was installed in a 1.5Ghz 15" Pb using instructions from pbfixit.com. The first thing I noticed about the drive was that it was a bit noisier than the stock Toshiba drive. You can hear the heads a little bit more than before. Not to bad but not a silent drive either, probably the second loudest part of the computer. The only thing louder being the CD drive when it is reading a disk. The second thing I noticed is that, now my fans seem to be running all the time now. Granted Powerbook fans are QUIET and make about the same kind of noise as the white noise producers installed at my work. So the noise is not an issue, the concern is that this probably means that the drive runs hotter or that I messed up the temp sensors when I opened my PowerBook. Unfortunately I never monitored my temperatures so I can't compare them to what they were before. That said it is noticeable faster than even my 5400rpm drive. I only have two programs that are at all hard drive intensive. X-plane there was a significant shortening of load time and the game played smoother than it had before. The biggest test I did was with Myst IV. If you don't know the game it is all pre-rendered graphics and you move from essentially one Quicktime VR (at least that is the basics, probably its own engine) scene to the next to get around. The load time from scene to scene cut in half from 2-3 seconds to 1-1.5. Makes the game much more enjoyable as often you are only in them for a second or two. Also since all of this is loaded from the hard drive it does a lot of work while playing that game. Despite the above heat concerns my laptop took 3 hours of the game easily and didn't get any hotter to the touch than I had remembered it getting before. The only difference being the fans were on more than before. Also, as I write this the fans are still running even though there is almost no disk activity. This is making me start to believe that the fan issue may be something I did when I was inside the comp . Better than having the fans not run when they should though. So if you have any ideas for what might cause it I would appreciate it. Sorry for the long post. Hope this is helpful, don't mean to scare anyone away from the drive, I love it .