I have tweaked a few more things, actually dropped to a 11x NB multi and then increased the FSB to 215, here is the current clock I am using, CPU voltage is set to 1.5 which is very high but doesn't seem to be the case of all of the voltage is at the CPU:
New highest benchmark score for a X4 965 and single RX470 of 9,610 - up from an initial average score of 8,692.3 so almost 1000 point improvement - mostly with the physics test.
I bought a stick of 1600mhz ram, however it doesn't seem to work so will try and return it - looks like I would only need a 4GB stick to run the benchmarks so could look to get a faster set of RAM however the small FSB boost seems to be helping.
Worth noting that the Extreme and Ultra Firestrike tests are actually easier on the CPU as its the GPU that's the limit and there are less frames being pushed to the CPU.
Highest temp I have seem during the benchmarks has been at 57C, most runs the max temp even at 1.5v is 55C which is the limit (max the chip can take is 63c though).
I can't seem to push past the current barrier, my goal was to try for a 4.25GHz setting which would mean a 25% overclock but running at over 4GHz is pretty good. Worth noting that I am able to keep a 4GHz overclock at around 1.45v just using the multiplier with the stock 200 reference clock. This seems the limit on mine at the moment, the BIOS on this motherboard isn't very good as I can't control the voltage directly - I am using AMD overdrive.
Worth also noting that every time the system won't POST I have to remove the graphics card to get to the CMOS jumper!