Let me know if you are interested in that or any other HP server hardware. The biggest problem with these is the size so shipping is a pain - even getting packaging big enough is a problem, so ideally you need to be UK based and even better middle of the UK!
I also have servers from 10 years ago with hex cores etc. Some I7 pc’s that when you run 3 plots its like choking them But we tinker… and make some plots.
This is the way to go, my main plotter which can do 20 minute plots is a Dell R620 with dual E5-2670 and about 384GB ram. Its noisy and uses a fair chunk of electricity but fills hard drives with plots.