Hard Drive is a Barracuda (ST2000DM001-1ER164) by Seagate, 2TB. HDD does run at 7200rpm, so it is a bit faster than the usual HDD's we're used to.
Hard Disk Sentinel shows the drive health as 35%. I repaired some bad sectors. Before it was at 27%. CPU is running at full speed (not underclocked due to performance). The computer is actually running normally as far as I can tell, no lag experienced so unsure as to what the client is talking about.
I am not 100% fluent with drive tech, does this imply it's failing? HDS says it is at an acceptable level, though I'd hardly consider 35% acceptable.