New Server Blade Build Advise Please

[Dizzee]

A friend of mine owns a data center and has said I can put a blade in rent free just paying usage costs. So, I would like to build a killer server, I'm aware it is easier to buy a pre made one but thats boring, and I'd like more control of what my box contains.

There is no fixed usages: I currently host a number of domains (about 25 odd) over several rented hosts that run nothing more than basic sites.
I will want to host a game: Ark survival (my current game vice), maybe with the view to rent hosting.
I will also want to stream audio, (I work with a number of sound systems and music creators / DJ's and it is something we have been considering).
I won't be cyptocoin mining.
Money is an option (like for everyone), but I prefer future scale-ability than concentrating on initial budgeting.

I've been hunting for a R4 (LGA 2066) dual socket mobo, but there aren't any? is it truly worthless getting an i9 server?

This leaves socket FCLGA3647 Xeon... any recommendations on a motherboard?

edit:
was first result: https://www.faceofit.com/socket-fclga3647-motherboards/

anyone know anything about POWER9 ?

what about this?? https://www.supermicro.com/products/...20/X11QPH_.cfm

[watercooled]

With that I think the first thing I'd be considering is adding plenty of storage to use for off-site backups.

For the stuff you've suggested, you wouldn't necessarily need the sort of processing hardware you've mentioned so far.

[DanceswithUnix]

For a cheap server at work we used a Ryzen 2600 in an Asus motherboard. Takes ECC ram, enough threads to run a bunch of VMs but *way* cheaper than a Xeon.

If you want to go larger, a Threadripper setup has more ram slots and can take more threads.

[moon_full]

When you say a blade server, do you mean a standard 1U/2U rackmount server?

Have you considered buying a refurb unit rather than cobbling one together yourself?