Have been having a bit of a play with this benchmark using different memory speeds.
I tested different memory speeds with my i5 3570k @ 4.6ghz. The benchmark was run 3 times at each memory speed, and the mean result of each part taken.
Every benchmark run has the exact same tertiary timings and only the secondary timings have been changed (tRRD, DRAM REF Cycle Time, tFAW and tWCL).
Results:
Memory Speed: 2133mhz 9-11-10-25-1T
Image Editing: 581
Encoding: 480
Multitasking: 971
System Score: 677
Memory Speed: 2400mhz 10-12-11-28-1T
Image Editing: 583
Encoding: 483
Multitasking: 997
System Score: 687
Memory Speed: 2600mhz 11-13-12-31-1T
Image Editing: 581
Encoding: 480
Multitasking: 989
System Score: 683
Overall, memory affects the multitasking part of the benchmark the most. The difference in the other areas either negligible or very small.
2400mhz proved to be the most efficient for me, appears that I need to run probably 2666mhz instead of 2600mhz but my ram needs loose timings for that to be worthwhile.
My best score so far is this:
CPU @ 4.689ghz (104.2x45) Memory Speed: 2500mhz 10-12-11-28-1T
Image Editing: 586
Encoding: 485
Multitasking: 1006
System Score: 692
Hope this info is useful