https://www.raptorcs.com/TALOSII
I just saw this, even if it is pretty old.
They continue the IMB powerPC architecture.
3mdeb develops coreboot for the architecture.
Here is an interesting presentation
OS Installation is complex, but Linux/BSD with support for ppc64 should work.
The used AMD Radeon Pro WX7100 GPU is pretty open, but the boot code contains blobs.
Just as the NVME controller.
This is a competitor to RISC-V, while the latter is in early steps but is high in trend and developing fast.
Yes it is pretty damn expensive.
3mdeb would be an alternative for people using servers, but they mainly to IOT and workstations I think.
And, no idea, but I assume there are server mainboards that are supported by Coreboot.
Afaik Google runs all their servers on Coreboot.
I as a mere mortal just spent reviving an “old” Thinkpad 250. I mean it had a 1TB SSHD in it, which never was full, a random old SATA SSD and it runs Xonotic!
That BIOS is 3 years EOL, and has strange settings, like not enabling TPM 2.0 or 2 strange remote management / antitheft services baked in, which could be permanently disabled.
Also disabling everything related to Network on the UEFI helped.