I have a Mac Mini not sure exactly which model most prob the late 2007 model anyways when I had to reinstall the operating system I had a couple problems installing it obv I did a clean fresh install....I was getting errors or some ****.....Once I have the OS installed I install all my programs and stuff I install an application called Drive Genius in which I have on my MB and I used it plenty of times all successfully with no problems and it does make your computer faster to open up problems and all and boot.....When I perform this on my Mac Mini it says defrag fails and then when it reboots it goes into kernal panic this happened 4 times.....?? ughhhhh Im guessing it is a hard drive issue can anyone here agree with me it wont even scan to check for bad sectors....?