Chances are that if your buying the motherboard new than it will have a later BIOS version than it had at launch. So the last BIOS updates for most P8 series Motherboards were around Q2 2012. So This particular Motherboard BIOS version 4103 enables support for existing Intel Core 3rd gen Ivy Bridge CPUs.
http://www.asus.com/Motherboards/P8H61M/HelpDesk_Download/