I have a 5810 and have upgraded the RAM to 256GB and the CPU to a 16-core / 32-thread. I use this for work to run large-scale computations. Occasionally when I'm running the cores and memory hard, I'll have a unplanned reboot which can cause me to lose hours of work. I assume this is the power supply failing. The spec sheet says it can take 425W and 685W, are there are any higher PSUs it can take? What models should I be looking at?

Likewise can I upgrade the heatsink beyond the base model?  CPUID HWMonitor is showing the cores getting pretty warm (up to 77C) when I'm only running 20 threads.

TIA