4850's in crossfire...Works but need help

As the thread name says my new setup does work - but I don't think it is working to its fullest and I don't quite understand why. I want to say it is the PSU, but I hope not because ... well I hope it is software based because I don't want to spend money  

System:
9850 BE
2x 4850
K9A2 Platinum MSI mobo
2 gigs of Corsair ram (XMS 2 6400)
100 gig (for now) Maxtor sata hd
And windows XP SP 2 ... Also Running the 8.7 drivers.
600 Watt Enermax Noisetaker PSU

Anyways, I know crossfire is working going by pure FPS differences in 3dmark06... almost a 20fps Difference if not more... however with crossfire on, and all settings at max I am only scoring a 12000... I would think it should be higher than this ?

I was under the impression that having the settings maxxed out would actually make the system run more smoothly. Age of Conan also benefits with crossfire on, but not by as much as I had hoped. There is only about a 5-10 fps change.

I am begining to think that I forgot something? I don't see anything in the bios that I can change to make things run more smoothly, And both the cards are running at 16x 2.0. Both cards are fully seated, powered... and I have the fans running at a modified percent to keep them from erupting in flames, both when I am gaming (70%) and when I am in idle (30%).

Anyone have a setup like mine that would care to explain why this doesnt seem right  .

Any feedback would be fantastic

-Zuk