For our test setup, we used our favourite ASUS ROG Rampage IV Extreme motherboard equipped with a water-cooled Core i7-3960X running at 4.8GHz. We have active cooling for the rams and VRMs to dissipate the considerable amount of heat when overclocking.
If you have plenty of time/patience to experiment and have the technical know-how, there are plenty of memory tweaking options on this board (timings, sub-timings, signal and voltages) to keep you occupied on lonely nights.
With a recent utility like AIDA64 or CPU-Z, we can read the SPD/XMP (Intel Extreme Memory Profile, a JEDEC SPD extension for DDR3 SDRAM DIMMs) settings programmed into each memory module. During our testing, we tightened the DRAM command rate to 1T instead of the XMP default 2T.
To highlight the advantages of using higher speed rams on our benchmarks, we pitted the G.Skill against run of the mill 1333MHz value rams (with a rated latency of 9-9-9-24), and then also overclocked it at a JEDEC compliant 1600MHz 11-11-11-28.
AIDA64 Memory Benchmark
Linpack HPC Benchmark
Left 4 Dead 2
The use of lower latency/higher frequency modules does play its part in CPU and memory intensive scenarios like content creation and heavy I/O operations, not so much in gaming where the bottleneck is usually the graphics card.