Hey there, I have a mac, Power PC running Panther (its the highest OS I can get it to run) and I put a 500 GB Seagate in it, and sure enough, same problem. 128 GB. You guys seem to be running down the problem on windows, but does anyone know anything about Mac? Unfortunately this is the Only thread about this topic I can find anywhere. If anyone could help it would be greatly appricated.