Aqua-Soft ForumsIf files are spread throughout the drive, the "pin" (or whatever it's called) requires more time to access files as it has to move back and forth. That's why it's good to keep your files as close together as possible. On the other hand, if you have a fragmented file, the drive's pin needs to jump around and gather its fragments.
Operating systems and apps that need to access the hard drive frequently benefit from a hard disk that keeps its files as close together as possible and defragmented. It seems that Windows focuses on keeping files tight together and OSX avoids fragmentation. A good defrag program will help in any case, although I don't know how much it would improve overall system performance.
Have a nice day!
Ken