Which CPUs does the MZ23-SU0 support?

One AMD EPYC 9005 series processor in the LGA 6096 socket, with a maximum cTDP of 500 W. Older EPYC 9004 chips use the same socket but are not listed as supported.

How much memory can it take?

Twelve DDR5 DIMM slots, running at up to 6400 MT/s. That is double the slot count of many single-socket boards, which matters for memory-heavy workloads.

Is 1 GbE networking enough?

Only for management and light traffic. The two 1 Gb/s ports and the management LAN are fine for control planes, but production data traffic will need a PCIe network card in one of the five Gen5 x16 slots.

What can I put in the PCIe slots?

Five x16 slots, all wired for PCIe Gen5 x16. That is enough for multiple GPUs, fast NICs or HBAs, which is the board's main advantage over rivals with fewer or slower slots.

Are the M.2 slots fast enough for a boot drive?

They are PCIe Gen3 x2, so they cap well below Gen4 or Gen5 NVMe drives. They work for boot and OS drives, but heavy storage should go through the PCIe slots or SATA.