Welcome back chaps (Andy and farmerboy). Farmerboy I can't fit both rigs in my sig so the AMD rig is now as follows:
8320 @ 4.8 Ghz 24/7 but tested to 5.2 GHz IBT stable
Crosshair V Formula Z
8 Gb G skill Ripjaws Z 2133 MHz 9-10-10-29, also used 8 GB Gskill Trident X 2400 MHz 10-12-11-30
7950 HIS ICEq boost
Best cinebench R15 score=829 at 5.15 GHz - out of interest, just looked and that is the top 8320 cinebench score on hwbot in world rankings and behind 3 8350s. I do think these chips can give more:
http://hwbot.org/benchmark/cinebench_r15/rankings?cores=8#start=0#interval=20
since you have the same board and cpu, would you mind sharing your bios settings to see where i may be going wrong / improve? this 4.9ghz wall is driving me mad