Goats in the Machine
I think my hardware is conspiring against me.
First, my decade-old Logitech MX 518 mouse starts crapping out while I play Overwatch. Thankfully, it's happening more and more frequently, and also on my Mac (which shows relevant "resetting device due to IO failures" errors in the console), which made this way easier to troubleshoot and identify. New mouse is on the way.
But this means I can't look to problems with the mouse (which I originally thought was a symptom) as I debug possible hardware issues with my new PC. Windows 10, including the recovery tools, crash a few minutes after the system boots. MemTest86 says it's not the RAM, so it could be the motherboard, GPU, or HDD. Early signs point to the GPU: it ran for several minutes, including an Overwatch bot match, when I took the GPU out.
I don't have a ton of modern hardware outside this machine, so I can't do a lot of part swapping to isolate bad components. I should have a new USB thumb drive in the mailbox today, so I can at least try an alternate OS install to isolate the HDD or deep-seated problems with my Windows install.