|If it was me, I would run a memory test for a couple of hours, at least. Any failures at all are not acceptable. If you have more than one RAM stick, you could try one alone.|
Another thing to try is downloading a diagnostic from the hard drive manufacturer's web site. I would suggest doing a complete scan of the drive. It will take hours on a 320gb drive. I know the old drive does the same thing, but ...
If you have access to another optical drive, it would be something to try.
Check for other suggestions that might be posted.