Hi, well after buying a maxtor diamondmax plus 9 200gig ata133 and then finding out that it makes horrible cliking noises i am going to send it back.. (if anyone has any idea why this would happen.. it only happens when i try and move data between partitions??) .. does anyone know how much real world performance difference i would get from between an ATA 100 and ATA 133 HD? (my mirrored door G4 takes ATA 133 HDS - but the seagate HD that comes with the computer is only ATA 100). Does anyway know which makes of HD's are really quiet? the seagate one allready in the computer seems pretty quiet and makes no cliking noises. andy.