Asus Rampage IV Extreme Motherboard Review

As with all of our reviews, we pit the default speed system against the overclocked one in a head-to-head byte match.  To make things a little more interesting we broke out the Single Stage Phase cooler for these tests so we could really dial up the CPU clock. (Sorry no LN2 this round) The effective overclock is 5.2GHz @ 52x multiplier and 100 BLCK. 

The results are show below.

Overclocking the Sandy Bridge E platform is very similar to overclocking on Sandy Bridge with one exception, the baseclock multiplier.  Base clock (BCLK) is still tied to the PCI Express bus so you are limited by how high you can go depending on your CPU and motherboard.  To further enhance the overclocking experience Intel has added a BCLK multiplier allowing you to fine tune memory frequencies and system clock
 
We didn't spend too much time tuning the R4E on Single Stage and really wanted to find out how fast this chip could run at around -30c, and as it would turn out 5.2Ghz @ 1.45v seemed to be the magical number.  Intel claims that 1.4v is the upper limit for "safe" voltages meaning that beyond that you could really damage your CPU.  This is one reason why SS and LN2 are used by overclockers, not only can you get the chip temperature down but you can overclock higher with less voltage and begin to push the limits of the CPU

The charts speak for themselves when it comes to performance, sadly unless you have a Single Stage Phase cooler in your chassis running this fast might not be realistic in a 24/7 situation.