It sounds like you may have a problem, other than the drive. We've used loads of 500GB Seagate drives, as well as many other manufacturer's and only have problems if the drive itself is defective. So, first you should run the manufacturer's diagnostics on the drive, just to be sure. Another thing to try (after you do that) would be to replace the factory IDE cable with something that is better quality (practically any ATA/66 or ATA/133 cable will work fine). Beyond that, it is likely that its a problem with the unit.