well i almost hav enough money to build my new gaming system but it seems my budget is growing due to a few amazing deals im getting from 1 of my dad's coworkers. i was just wondering, is it worth paying the extra cash nd getting a 4000 or shuld i just stick with a 3700 (both san diego cores). my main concern is that the 3700 may cause a bottleneck for the 7800GTX im getting. how much of a difference wuld the 4000 make over the 3700 in terms of game performance and gfx bottleneck?