Make yourself a copy of the most recent Ultimate Boot CD (burn it as an image)
It's got manufacturers' diagnostic software for several brands, as well as other useful stuff.
Run the long test on that drive.
See if it's the drive itself or the software on the drive.
If you get a new one, you can do a lot better GB/$ wise with a bigger drive, up to 1 or maybe 2TB.
"I am altering the deal. Pray I don't alter it any further."
Darth TiVo, 14 February, 2011