A friend has a Mac Pro for a year now. He would add 3 more drives and had one who would not mount easy. It took 30 minutes to appear. He went back to the shop to ask for a new one. They would test the drive first. They told him that the drive was OK. He got almost a fight. Later he switch one of the 2 other drives he bought to bay #3 and got the same problem. That bay #3 has an error in hardware (I think) Luckily he also had the Apple 2 year extended warranty. He will bring his Mac to the dealer for repair. The moral of this all is that when you've a Mac Pro test the drive bays within the first year if you don't have extended warranty. Paul Moortgat