I went to the store today looking for an internal and external HD for my PowerMac G5 dual 1.8GHz PPC. I am running 10.4.11, but will soon upgrade to 10.5 (Leopard, as I cannot run Snow Leopard with the PPC). After reading the description in all the boxes it hit me that they all said "Compatible with Windows Vista/XP/2000". Are internal and external HDs made specifically for the Mac? Or will any HD work? I am looking at the WD Caviar Black (SATA, 3 Gb/s, 7200 RPM, 64/32 MB cache) for internal. However, I also saw an internal WB Velociraptor (SATA, 3 Gb/s, 10,000 RPM, 16 MB cache) for $269. Is it worth it? For the external HD, I am interested in partitioning it into two parts: one to have backups of portions of my HD (image and music libraries) and the other one for Time Machine. Is that possible? For external, somebody suggested the WD Caviar Green. However, all I can see is "My Book Studio", "My Book Studio Edition II", and "My Passport Studio". Any suggestions/ideas? Thanks!