tkin
Back to school!!
Check the latencies, compatibility issues may arise.BTW , for MAX-ing up the four ram slots- can two gskill rams 1600mhz each in dual channel...and two corsair vengeance sticks of diff. size but same 1600mhz be used in full dual ch.configuration ( all 1.5v for SB rig )??
We can still increase it by 2-5MHz on good mobos, like asus z68 vpro.Bclk is generated by the nothbridge,so yes you do need good phases on your mobo to increase it.
The problem with sandy bridge is that the bclk has been combined with the rest of the clocks that control SATA,PCIE,USB etc frequencies so any increase can damage these components.
However RAM can still be overclocked by increasing its multiplier.But that will mean you will need excellent RAM to OC because it will be straight jumps from 1600 to 1800 or 2000 etc.