Need some help understanding sli settings

Hi I just built my first sli rig my specs are MSI NF 980-g65, twin EVGA 9800gts overclocked, 4 gigs patriot ddr3 1600 ram, AMD 955 BE, and a western digital 7200 250gig sata drive.

Here are my questions I built it for gaming and on 3d mark 06 it scores 18000 in standard sli and in Battlefield BC2 averages 75FPS with my settings almost all set to high. Afterwards I went into the bios and turned on the hybrid sli and rebooted the system. Now in the NVidia dash board and in evga precision I am showing 3 video cards 2 9800s and one 8400 which is the onboard. My first question is it really active? I went in the nvidia dashboard and dedicated it to physx then benchmarked again. I saw no increase in 3dmark 06 but had a big frame gain in Battlefield BC2 from 75avg to 110fps average. Second and third question is does this make sense and why is there no difference in 3dmark?

yes if hybrid is active it will use the onboard video in a tri sli setup. as for 3dmark scores I know it doesn't count physics at all so you could have your cpu or any gpu set to handle physx and the score will be the same, I thought I read that disabling physx while running any of the futuremark software increases your score slightly but I'm not 100% sure on that one.