As far as I know, these cards use the GA102 chip, it's the same as used in 3080 and 3090
Here you can see the list of all gpus using this chip (CMP 90hx included): https://www.techpowerup.com/gpu-specs/nvidia-ga102.g930
It's not too old, but it's the generation of 3xxx, and it's not an easy gpu to resell like any other standard GPU.
If the price is very good and the electricity is cheap, maybe it's worth it, but you have to do the math with your friend.
In general, I think there are video cards that can be better these days. Like the Nvidia 4070 that will be released in a few days.
Good to know, thanks