Really? Wow... What do you mean by maxed out, how's your setup?
Vegetation (from launcher), unit size, detail levels, anti-aliasing ...?
I am genuinely interested to hear more. My setup is very much the same with dvk's apart that my AMD quad CPU is only 2.6 GHz.
And that is an issue, I tried huge unit size for a while but I am back to large as there tends to be a lag when fighting two full stacks.
The sweet spot is somewhere around 2.9 - 3.0 GHz it seems.
Forgot to add: No, I can't OC. W7 64bit. MS Security essentials for virus control.