There you are:
replace your /Extra/Extensions + Boot plist + SMBIOS plist by those in the attached archive. you probably have PSMenu in /Library/LaunchAgents, delete it, it'll no longer be required because you'll now have native CPU and GPU power management. run myFix (quick) and reboot. if you have IDA enabled in BIOS, disable it (you have a Merom CPU).
Tuned_Archiv.zip
Use the attached HWMonitor app if you want to monitor CPU+GPU T°, speed, voltage, etc. It goes with the tuned FakeSMC you'll now have.
HWMonitor.zip
PS: you can safely update to 10.8.5.