I have 6 Haswell (2013)-era Dell Optiplex computers that are the kids' Minecraft (and YouTube) computers, the living room TV source, my non-work PC, an electronics lab computer (with a GPIB interface and general look-crap-up usage), and a PC in the guest room [which also serves as an additional video conference PC when multiple of us need to take simultaneous calls].
I got two of them right as the pandemic started for the kids, paying around $150ea, and got the other 4 earlier this year for $90 ea with i7-4770 or 4790, 8 GB of RAM, and an OEM Windows license. They'll all run Windows, Linux, or macos (Hackintosh) as needed. Some I've upgraded to 16 or 32 GB of RAM. All got a modern SATA SSD. So, I've got 6 working computers for under $1300 total. They're not speed demons, but they're perfectly usable and can drive multiple 4K displays at 60 Hz.
I got two of them right as the pandemic started for the kids, paying around $150ea, and got the other 4 earlier this year for $90 ea with i7-4770 or 4790, 8 GB of RAM, and an OEM Windows license. They'll all run Windows, Linux, or macos (Hackintosh) as needed. Some I've upgraded to 16 or 32 GB of RAM. All got a modern SATA SSD. So, I've got 6 working computers for under $1300 total. They're not speed demons, but they're perfectly usable and can drive multiple 4K displays at 60 Hz.