Maybe try your local Pc store see if they have a 2500 and will help out?
or get the old one back temporarily if you can?
If you are in the UK, http://bios-repair.co.uk/Programmed-BIOS/Asus/LGA1155-Asus.html
I'll try and find a US vendor as well though
**Edit, found this guy, http://www.badflash.com/