Don't know a great deal about mining but I'll try to learn as I go
First off, all the recommended MB's are unavailable, I've found this
Asrock FM2+ MB that can only take 5 GPUs.
Although this is a mining MB,here is little to no info about it used in mining so I don't know if this is such a great idea.
Also, will a good 850W Corsair/EVGA Gold PSU be enough for 5x RX480 4GB setup?