thi is pretty much the same system I build in 2009.
The bottleneck will be most probably your Bloomfield in default clock.
That said you should seriously consider to lift the clock of the I7.
If you are using the boxed cooler you will be able to get 3 Ghz without any probs, should be 3.2Ghz.
The cores` max temp is given at 102°C by intel , so much more than common mondern cores today and even more you will ever reach or need.
If you got a more decent cooler or even a AiO cooler you should be able to gain 3.99 - 4,2 Ghz.
As I got aswell an Asus Board in those times and the same core, although different RAM I could give you my Bios values.
That way you can move step by step to a suitable core clock of your I7.
Leaving the 920 at 2,66Ghz is actually a sin, when you invest for remaining hardware updates.
BoS,Clodo and Arma3 e.g. profit much more of CPU power than one may suppose.
However there are so much tutorials in the web for clocking the I7 920.
Easiest step with a boxed cooler without changing the voltage, is moving your BCLK to 150 and setting the multiplicator on manua in your Bios. 150 (BCLK) x20 (Multiplicator) = 3000mhz (Core clock)...using this lightweight of core clock is apperantly your duty
If you are interested to keep an eye on the temperature use "RealTemp", however it is not needed in this area of clocking.
The screenshot of the bios below, serves just to link you the way. Dont use the settings. You navigate to the AI Tweaker section, set the overclock tuner on manual and lift the BCLK frequncy to 150. Press F10, job done. No risk but more power/FPS for 5 clicks .
I got also a velocity raptor, formerly my OS HDD, right now it became my data grave on demand.
I always prefer the clean solution. Use a SSD install your OS and game to it.
If you like to keep your old system on the Raptor for copying things from on to another and fomat it 2 weeks after for proper use.
As for your HD6970, which is a nice card - used two of it in my rig those days - but it is also predestinated for clocking - not again... you will maybe think.
But with MSI Afterburner it is quiet easy to lift it for around 10%, even with its default fan.Your default clock of the 6970 should be 880hmz depending on the version, its mem clock is at 1375mhz.The screen attached below shows the last stable configuration I used.Quiet handy tool as you are able to monitor each components.
If you need help ,let me know.
My two german pennies.