Chris,
I am a new owner of a Crosshair V Formula-Z. I have been trying to OC my FX-9590 for a few days now and my PC kept freezing up on me after 1.525v or 5.0GHz, even doing such simple things as going on the Fraps website (because of flash video, as you have stated). I have been tearing my hair out over here trying to figure out why this was happening, ripping through BIOS settings and flashing different BIOSes. I have been lurking the ROG forums for a few days now trying to find any info to help me. By luck, I stumbled across this thread you made.
I have re-enabled my core parking (it was disabled from that Windows 7 Bulldozer hotfix) and disabled C6, and it fixed my issue immediately.
I literally made an account here to thank you personally. It may not mean much to you, but your tip has helped me out tremendously. I was getting so frustrated and confused there for a while. Thanks again!