I am planning to build a multipurpose home server. It will be a NAS, virtualization host, and have the typical selfhosted services. I want all of these services to have high uptime and be protected from power surges/balckouts, so I will put my server on a UPS.

I also want to run an LLM server on this machine, so I plan to add one or more GPUs and pass them through to a VM. I do not care about high uptime on the LLM server. However, this of course means that I will need a more powerful UPS, which I do not have the space for.

My plan is to get a second power supply to power only the GPUs. I do not want to put this PSU on the UPS. I will turn on the second PSU via an Add2PSU.

In the event of a blackout, this means that the base system will get full power and the GPUs will get power via the PCIe slot, but they will lose the power from the dedicated power plug.

Obviously this will slow down or kill the LLM server, but will this have an effect on the rest of the system?

  • partial_accumenEnglish
    7•6 months ago

    You could accomplish what you’re trying by putting the GPU in a second computer. Further, most UPSes have a data interface, so that you could have the GPU computer plugged into the UPS too, but receive the signal when power is out, so it can save its work and shutdown quickly preserving power in the UPS batteries. The only concern there would be the max current output of the UPS in the event of a power outage being able to power both computers for a short time.