No idea, like I said I'm not 100% on this. Regardless, the link I posted got a 3dmark of 23,000 and the new record is only in the 25,000's so... couldn't be much of a difference.
Yeah, I've seen Pentium 4s at 8Ghz with liquid nitrogen and other extreme cooling. Once heat isn't a problem you can find the physical limitations of the hardware.