So, right out of the box I ran this Ridgeback set of memory at 133Mhz (2133MHz) higher than the rated specification with the same timings. To reach higher speeds than 2133MHz I had to use a combination of timings, voltage and blcock tuning to reach the final clock speed of 2252MHz or 252MHz over the rated frequency. For voltage, I had to push 1.69v through the modules to get 2252MHz stable. Tightening the CAS latency any more than 9 at this level resulted in the computer not posting. To reach a CAS latency of 8 with sane voltages. I had to drop to the 1866 multiplier and increase the bclock so that I could run just over 1900MHz at 8-9-8-27. CAS 7 took another reduction in frequency to to around 1684MHz at 7-8-7-24. Even when the CPU multiplier was increased to run the CPU at a higher speed to increase overall bandwidth, I did not see a significant increase in memory bandwidth from 3.4GHz to 4.7-4.8GHz in SiSoft Sandra 2011's memory bandwidth test. In the end, a 12.5% increase in clock speed offers up performance improvements but are tempered by the fact that the CPU is overclocked at the same time.