Hi,



HERE is the dummy.kext that will fix SpeedStep when MacPro4,1 is used as model name(Smbios.plist injection).
Put it on your /Extra/Extensions.mkext(is a must!)
Works on both leopard/snow

*Edit:

I saw EvOSx86 team has a similar fix HERE
Use whatever you like, the dummy.kext does same thing, is not yet a full fix(MacPro4,1 use diff method) is just a trick to force SpeedStep to work as was for MacPro3,1(used as model name)
For me works w/o _CST method fix, if you experience any problems try that fix.