I have the exact problem with Rev 2 and can not figure out how to fix. I had a Time Machine backup of my Rev 1 system, so I reinstalled Rev 1, and transferred my Time Machine backup and everything is now back to normal. I'll wait to see if anyone comes up with a solution before I reinstall Rev 2. Rev 1 works perfect on my DFI Lanparty NF4 ULTRA-D/Operton 170 at 2.7/NVidia 6600GT/SATA HD/PATA DVD.