They are indeed Inventec B800. I have been running one for slightly more than 1 year with ESXi and they are rock solid. I got my board from the same ebay seller. They are very decent and good to do business with.@Klee The first board looks to be an Invetec B800, if so they are, generally speaking, reliable. They are decent value for money no frills entry level boards, but support is all but non existent. The good news is that pretty much everything on Invetec boards is off the shelf, so Chipset manufacturers are carrying the support load to some extent. I have no experience with that x79 board, but the Realtek nic's would kill it for me. It's still probably decent value for money though, depending on what you were doing with it
I reached out the engineer in Taiwan for an updated BIOS but they simply didn't have any updated version. Those are indeed OEM boards so per the engineer if the client didn't pay for updating the BIOS then they will not spend resource on those tasks.