Thanks for the information, I have made a link to this post in topic start.
The information about migrating the A2 folder to the outer platters is exactly what I was looking for. Once I have done this I will report on what changes I have noted.
I did post a program called TuneXP 1.5, I believe that allows you to increase IRQ handling speed, and USB polling interval.
Regarding BIOS tweaks, I found that in ArmA1 disabling Coool'n'Quiet did increase performance, sometimes, but not all the time. In ArmA II the performance difference is marginal for me, and CPU can reach temperatures up to 50celcius due to my crappy thermal grease I'm using atm. However, since the performance increase I've noticed is so small then I rather choose to keep cool'n'quiet on so that temperatures stay in the 30s and low 20s when idling.  I ahve also disabled microcode updation as I have read in places that it slows the CPU down.
playing with cpucount and arma2mark:
Wtf @ cpucount=3? A drop in performance. I ran that test a few times and got similar results.
Running on phenom II X4 @3.4Ghz