Sussed it! The BMC is trying to connect to a server. Disabled the BMC and its boots relatively quickly.
Now I’ve read some more on the BMC I understand what it is.
I turned it back on in the BIOS and put a random address in (192.168.100.90) and it still boots OK.
Sadly the documentation for this motherboard is extremely poor.
Have built a system with above mobo, my old box had ASUS X-99E with 2 Quadro P5000’s in SLI. The MW83 has 7 slots but no mention of SLI ready in specs as do most (all?) new W790 mobo’s
I’m loathe to bin the Quadro’s as they work very well, meet my requirements & RTX cards are more expense.
Anybody else use SLI on a new generation mobo with experience of working, non-working or BSOD misery?