you will more than likely need a 920 to update the bios, i got an asus p6x58d-e with the old bios and i couldnt get it to work without putting a 920 in it even after replacing the bios chip with one with the latest bios on it.
also looking at the odd bit of computex coverage, specifically x299 motherboards of course, they say they will either support the core X or xeons. are they going to be made totally incompatable? before you could drop an extreme edition i7 or a xeon in any x99 board (within reason) workstation or not. itll be a shame to not be able to stick xeons in consumer boards anymore if that is so