Just trying a few different RAM setups now, here are a few results now that I have some faster RAM:
4GB 1333mhz ram - 9 9 9 24, 215 x 19 CPU - 9560
4GB 1600mhz ram - 11 11 11 28, 215 x 19 CPU - 9239
The 1600mhz 4GB stick has looser timing but it seems I can increase the FSB higher if needed, managed to get to 230 x 17.5 but found that it wasn't 100% stable for a benchmark.
Also then tried simply running a single matched set of 2 x 4GB Corsair 1333mhz RAM - 215 x 19 CPU - 9675 on Firestrike which is a new record!
I am going to look to see if I can bump the FSB slightly more with the current timings to see if the matched set of 2 x 4GB might give better performance.
I also have my X6 1090T CPU on the desk to drop in over the weekend, will be interesting to compare but wanted to get the most out of my current system, still can't hit 4.1Ghz yet but close!
Edit - ha, increased the FSB by 1 to get 216 x 19 = 4.105Ghz, now to see if it will run a benchmark!