Yesterday I got my new mainboard, an Asrock Fatal1ty B85 Killer. The first thing I did was upgrading the BIOS to the latest version available (V1.30). Next I wanted to patch it with PMpatch in order to unlock the MSRs but I was very surprised that PMpatch didn't found a match pattern in the power management module. This made me curious and I tried to boot Mavericks with the vanilla BIOS and it succeeded. No KP, no early reboot.
Obviously Asrock has decided to change their policy with regard to the CPU's MSRs in some of their latest BIOS releases for at least a few of their boards because I don't think that the Fatal1ty B85 Killer is the only board with unlocked MSRs. I wouldn't be surprised in case other members of their Fatal1ty series of mainboards are affected of this change of mind too. It would be great if anybody with access to one of these boards could confirm this.
I downloaded the BIOS files of the following boards from Asrock's website and tried to patch them with PMPatch but it didn't find a matching pattern in any of these BIOS files. It looks like all these boards have unlocked MSRs too. Well, it might also be the case that PMPatch lacks some matching patterns but you would need a board in order to verify this.
- Asrock Fatal1ty H97 Killer (Version 1.10)
- Asrock Fatal1ty Z97 Killer (Version 1.30)
- Asrock Fatal1ty Z87 Killer (Version 1.40)