I have lots of hard drives that I believed to be faulty and beyond repair. None of these drives made physical sounds to indicate the perceived failure but for one reason or another would not function properly. Some would hang in the OS at some point, some would loop with a check disk failure of some sort and others were just generally quirky. For testing I've used Cyrstal Disk Info primarily. Also event viewer is useful.
I began reading that some of the errors like, pending sector counts could be cleared with a zero fill. I decided to try this using HD Tune and wallah! Now a few of these failing drives, all that I've cleared so far, pass with flying colors when I test with Crystal Disk Info.
In the first test I've completed I created an image of the possible failing drive using Acronis. I then zero filled the hard drive with HD Tune. Once complete and passing Crystal Disk Info I then recovered the image to the repaired drive. This particular drive only had one sector with problems according to CDI. The problem of general slowness and up and down performance is now gone with the above fixes applied.
Was that all it took? Could this large pile of TB's upon TB's I have really be useful again? Most of these drives are cheap drives that come in new consumer laptops and desktops. Any and all advice is welcome. Thanks in advance.