You'll see a more realistic result from 3Dmark 2006 as that takes advantage of the dual core CPU, 2005 doesn't.
Here at work I've got an Athlon X2 4800 2gb Corsair XMS memory and Crossfired Radeon X1900XTs. It benchmarks 8210 in 3DMark 2006 and 12549 in 2005. It was the fastest machine in the office until I put together two systems last week with the same setup only two nVidia 7900GTX in each. They benchmark 8759 in 3DMark 2006 and 12811 in 2005.
I've been playing Half Life 2 again recently with everything maxed out, god it looks stunning. So crisp and clear. I'm looking forward to Episode 1 which is out the start of next month. Mine is already pre loaded and ready to go.