Today, I updated the i7 920 Nehalem quad core processor in my ASUS P6T based Hackintosh to an even more spiffy 970 6-core Gulftown CPU. Since the i7 970 was retired and discontinued (EOL) recently, prices for the leftover stock have fallen sharply so I decided to get a new one as long as they’re still available. If you own an ASUS P6T make sure you use at least Bios rev. 1303 or the mainboard won’t recognize the 970.
Upon booting OS X I noticed that P-state P0 a.k.a “Turbo Mode” wasn’t working anymore with the new hexacore CPU on the mainboard. In order to get Turbo Mode back, I needed to edit Chameleon’s com.apple.Boot.plist. Here’s what I added:
<key>GeneratePStates</key> <string>Yes</string> <key>GenerateCStates</key> <string>Yes</string>
With these settings Chameleon automatically takes care of the C-states and P-states for the CPU. Very cool, that saved me a lot of time messing around with the DSDT! You need at least a recent Chameleon version like RC5 though, the last official release from 2009 won’t support those properties.
Here’s the Geekbench score of the updated rig: