Try dropping the multi to 10, set FSB to 1600 and RAM to 800. This will be 1:1 with CPU-Z reporting that your RAM is running at 400mhz. (400 x 2 = 800 DDR2.)

With 1066mzh RAM rated for 2.1v, you should be able to tighten timings at 800mhz to 4-4-4-12 while keeping a 2.1v voltage. Honestly, there is really no reason to have RAM rated higher than PC-6400 / 800mhz unless you are pairing with a lower end, lower-multiplier chip.

It's hard to comment on your 3d mark score w/o knowing more about your setup. With the specs in my sig and the proc at 3.6ghz, I hit 18,300 in 3DMark06.