Don't forget that a single core on a modern CPU might be 4x faster and use 4x less power than an old xeon. Old server gear is cheap because it's slow and costs heaps to run - make sure to budget for ongoing costs too.
I reduced my servers power consumption from $5 a day to $1 by replacing 2 2667v2 machines with a single i5 12500 machine... And it's significantly faster. My servers main use was Plex and at $150~ a month to run it was cheaper to be subscribed to Netflix, Disney, Stan, binge etc every month vs leaving the old gear on.
I use a p4000 to transcode Plex content. The GPU uses less power than maxing out my CPU. I also have the GPU available in Kasm though I'm unsure if that works as I mostly use kasm as a SSH jumpbox or access to an unfiltered Chrome session at work.
When I upgrade my CPU, I plan to put my spare 1650 in my host and spin up a windows gaming VM for guests and remote play.