Also... SB's didn't ALL clock high. A lot of people were stuck at 4.5ish. Claiming that they nearly all went to 4.8Ghz is BS.
You are 100% right. I can't find the scores for my original 2500K, but it would not go beyond 4.4GHz regardless of how many volts was put into it upto 1.5 volts.
I could do a suicide run with the one below at 5.4Ghz @ 1.5v for super pi, that's about it, not stable at 5Ghz with 1.5v even.
EDIT: P67 chipset motherboards overclocked sandybridge CPU's better than Z68 and Z77 with lower volts, I can only assume it was because P67 didn't support integrated graphics.
I wish I had kept my Gigabyte Z77-UD5H, it would let my 2500K clock to 4.8GHz with 0.2v less than my MSI Z77 MPower, it still wasn't able to do 5GHz though fully stable.
MSI Z77 MPower
2500K: Batch No: 3138A838
4.8GHz = 1.326v load (prime95), 1.32v load (IBT 2.54) 1.352v idle. (Manual CPU Voltage = 1.36v BIOS)
MSI GD65 Z68 (G3)
2500K: Batch No: 3138A838
4.9GHz = 1.408 load (prime95), 1.408v load (IBT 2.54) 1.424v idle. (Manual CPU Voltage = 1.43v BIOS)
4.9GHz = 1.400v load (prime95), 1.42v load (IBT 2.54), 1.01v to 1.06v idle. (Auto CPU Voltage)
4.8GHz = 1.336v load (prime95), 1.344v load (IBT 2.54) 1.352v idle. (Manual CPU Voltage = 1.36v BIOS)
4.7GHz = 1.296v load (prime95), 1.296v load (IBT 2.54) 1.312v idle. (Manual CPU Voltage = 1.32v BIOS)
4.6GHz = 1.384v load (prime95), 1.408v load (IBT 2.54) 1.01v to 1.06v idle. (Auto CPU Voltage)
4.6GHz = 1.280v load (prime95), 1.280v load (IBT 2.54) 1.296v idle. (Manual CPU Voltage = 1.30v BIOS)
2500K: Batch No: L104A429
MSI GD65 Z68 (G3)
4.6GHz = 1.336v load (prime95), 1.36v load (IBT 2.54), 1.00v to 1.05v idle. (Auto or Manual CPU Voltage) (Maximum Clock stable)
4.5GHz = 1.328v load (prime95, 1.352v load (IBT 2.54), 1.00v to 1.04v idle. (Auto or Manual CPU Voltage)