Part 1: Why benchmarking always wins
One of my long-running hard drives seemed slow, and I had no idea why. I downloaded some SMART diagnostic tools (including DriveSMART and HDDLife, both very nice), and everything was fine. I even downloaded Western Digital's equivalent program, and it didn't give any better information.
Finally, I downloaded a benchmarking tool called HDTach and got a much more definite picture of what was going on. Multiple tests like the one shown here reveal the same "troughs" in my disk's performance, so I figured it was probably a hardware problem. I thought, if it's a software problem, these dips in performance would be more random. (And yes, before you ask, this disk is entirely defragged, and the machine is completely idle.)
I get funny looks when I insist that performance benchmarking is a secret view into correctness, but I keep tripping over examples, so I just want to underscore that point.
None of the available diagnostic or analysis tools could give me decent information, but a benchmarking tool told me I needed to pay attention.
Part 2: Norton Ghost doesn't come to the rescue
I had a spare identical drive around, so I popped it in and purchased Norton Ghost. After downloading, I found out that it's evolved to be quite a different product than I remember.
The new version seems to think that you want to do live system backups, instead of drive imaging, and it makes it very hard to do old-school drive images.
I persisted with it, though, and made a "Recovery Point". Rebooted to their CD, and everything would work fine *if* I left the same broken drive installed. But when I replaced it, Ghost wanted nothing to do with the new drive -- it wouldn't find my original image, and failed gloriously.
This leads me to say: who the heck has a catastrophic recovery system that requires replacing broken hardware with the exact same broken hardware?
Shame on you Symantec, and what have you done with my $70?
Part 3: Simple is better
So, since I happened to have identical replacement hardware on-hand, and I happen to know enough of Linux to erase all my data by accident only some of the time, I booted up Fedora Core's rescue disk, ran "dd if=/dev/hda of=/dev/hdb" and waited awhile. Of course everything worked great, and now my C: drive is fast again.