stress test/games won't utilize 8gb ram - disk usage 100%

Welcome to the forum.

There is nothing that would indicate a memory problem. Most likely the system memory manager hasn't assigned more memory to processes because more wouldn't significantly improve performance. Don't be misled into believing that only 5.6 GB RAM is being used with the rest being wasted. Open Resource Monitor and look at the memory tab. Likely a substantial portion of memory is in standby, which is good. This memory is by no means unused but is making a significant contribution to performance. Only memory labeled as "Free" is unused. The ideal value for free memory would be zero at all timed but we are not there yet.

Of course it is possible there is a memory problem but based on the information provided that doesn't seem likely.

Hm. Checked on that very thing, and you were right of course.

It also seems my disk read/write is still misbehaving, though. Startup boot, and the load times of several programs are still outlandish. In the midst of loading a game, my read/write constantly drops to nil, even though usage is at 100% at the time.

I've done a basic chkdsk and found no bad sectors. And if it's not likely to be a RAM problem, then the only thing I can think is that I'm being bottlenecked by some ridiculous HDD function. superfetch and windows search are still off, and since then it's definitely improved, but I don't know what else to try.

Most posts I've found online aren't very clear, or are solved after disabling the two mentioned culprits

Got Driver Easy, updated everything, including SATA/AHCI (and a number of other things i wouldn't have figured), restarted, but still no change. Boot time is still pretty crazy

Have you tried scanning your computer for any viruses? They could be culprits.

Done a full scan with Windows Defender (which took 19 hours total), ran HijackThis and analyzed, as well as CCleaner. Nothing suspicious turned up in any of the above.

Disk usage back to 100% regularly, with 0mbps read/write at odd intervals. Possibly HDD failure?

Possibly. What drive are you using to run these games on?

toshiba dt01aca050

Have you tried running full test with HDTune? Take a screenshot of it when it's done.