Right used empire EFI used retail snow leopard installed great but when I restart it comes up with boot mgr missing and won't boot only boots with the empire efi disk in ? Also my network don't work so can't connect to the net sound don't work too

Motherboard is MSI H67M AE35
Intel I7 2700k
Graphics is onboard intel HD was Radion but was told they not compatible so removed
Sound is on bored too

Do I go back to windows 7