hi im new here but i would like some help right now i have a bfg tech 7900gs OC i love it to death but i was thinking of geting a bfg tech 8600gts oc2 well the bfg tech 8600gts oc2 be better then my 7900gs OC thank you to who ever helps me
You could always try overclocking your 7900GS even more, I had mine at about 590Mhz core and 890Mhz memory without any additional cooling. I then bought a Zalman VF-900 and could get 600 core and 900 memory, and finally volt-modded the core(quite simple actually, there are guides online) to get 690Mhz Core and 900Mhz memory(didn't volt mod this, so no increase). You might find you can squeeze a bit more mileage out of it that way so you can save up for a true upgrade like a 3850, 3870 or 8800GT.
I don't think that 7900gs -> 8600GTS is a good upgrade since there won't be a very large performance difference. It would be money poorly spent. Either shell out more for a higher end card or wait for a faster card in the same price range.