@Everdying  -- Yes, most people are using dedicated sound card, but too bad, hahaha me is for 1 don't. I using the on board 1.

As for the dx11, my card dunno got support or not, is 8800GT. but since i using windows 7 so i able to set it to dx11 with no problem, but i do know that my card suppose doesnt support, and it will crash the game if some special for dx11 effect start up. (EG: AVP flashlight - crash my AVP when in dx11, but do fine in dx10.1)

During MP, i set dxversion to 9 cause for my rig, somehow it does have big fps boost about 10~20fps, and although got FPS drop during intense fight, the drop became much more playable. EG: with dx11, avg 50fps, then intense fight drop to 20fps. is worst than, dx9 avg 60 drop to 30 fps during intense fight. Get what i mean? The 10fps boost is sort of quite "playable" and "valuable" when the fps drops to lowest.

Also, this is the tweaks meant for people who have lower end rig. Higher end rig doesn't really need these graphical tweaks.