if it don't post you will then if it was enugh to display bios to flash can you trust that to be stable do a flash [ flashing is a lot of risk when things are working correctly]
if me I would just go with the 4670 - that's what I got on this z87 extreme 6
what do you really gain or loose ??
http://ark.intel.com/compare/75048,80811
look here at newegg and the boards birds eye view [magnified larger to see better ] look around the sata ports and the motherboard battery you see 2 white with black lettering stickers that have the factory shipped bios revision printed on them -- your board should have this as well
asrock is nice enough to do this so theres no guess work of what you got to start with and mistakes trying to guess