In the world of hard drive information utilities, HD Tune is a gem. A venerable one at that–it’s been around for years and no one has come up with anything better–except of course for its developers, who also sell a Pro version.
The free version of HD Tune is adequate for most purposes and gives you a rough estimate of your drive’s performance, scans your disk for errors, and retrieves the S.M.A.R.T. (Self-Monitoring, Analysis, and Reporting Technology) info from your hard drive. Said S.M.A.R.T. info (often reported by your BIOS at boot time) can tell you if your hard drive is about to give up the ghost.