Motherboards???

[Dredgen Apollo]

qusetion isnt valid anymore

[An0maly_76]

VRM cooling is a big deal with these chips. I run a 5900X with PBO on an Asus Tuf B550-PLUS, guaranteed to support it without cooking the VRMs. There is also the Asus Tuf B550-PRO, which has a USB 3.2 header handy for some cases. I've had good luck with mine apart from RAM QVL issues, which are something else you should be aware of. If it's not on the board manufacturer's QVL list for that setup, it may not be stable. Ask me how I know.

[heimdali]

You'll want something with ECC RAM, and that can get surprisingly difficult and expensive unless you go for older sockets like LGA1155.  Options to pick from depend on your budget and on availability.  It tends to be a lot cheaper to buy something like a Dell R720 than it is to put something together yourself.  For IPMI, check out Supermicro boards; or if you buy a Dell, make sure it comes with an enterprise licence for the IDRAC.  HP won't let you have firmware or anything, so their used hardware is bascially worthless.