Na you wanna go with the 260 core 216 by EVGA if budget allows and either the 9300 or 9450 then overclock up with a True 120 extreme (its mahoosive so case considerations are a must) or the sunbeam core contact freezer 120. Nvidia sli is better then current crossfire solutions although the 4870 is the best single gpu solution.Q6600 is old tech and the Q6700 is just a needless expense for the same tech when as a power user you can overclock. The Tpower is skt 775 and with the P45 chipset its quite modern. i reccomend you don't go creative Auzentech and the asus xonar are a lot better if they fit budget (I am in the uk not the hottest on US prices for obscure items like a soundcard). I have the Asus xonar D2X and its the first soundcard I have bought the difference is incredible!!! My speakers are still fairly generic and unaudiophilic but it has improved the sound greatly in all aspects.
Nvidia is coming out with new cards if you hold out but in the tech world I am sure you know there is always something rumoured to be better round the corner.