I also get x28 as the maximum with my 2670QM (patched BIOS, patched original DSDT [although PikeRAlpha's ssdtPRGen gives me 28 as max also]):
Screen Shot 2013-05-16 at 05.24.07 PM.png 69.64K
This probably isn't an OS X problem, however; 2.80 GHz is what seems to be reported under Windows, too:
Screenshot (4).png 42.98K
This thread explains (I think) why.
qwerty12Member Since 06 Jun 2007
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