i don't think your gonna notice a difference in games between a 7800gtx... thats highly overclocked, and a 7900gtx... maybe in games like quake for on ultra settings that require it... but i dunno about most games... but i understand ur needs... i too am not 100 percent satified with the 7900.. why... i don't know? i just wanna beat my friends comp..
Intel 3770k @ 4.4 GHZ | Galaxy GTX 770 SLi | 16 GB G.Skill Sniper | ASrock z77 Extreme4
2xSamung 840pro 128GB in Raid | 2x1TB Seagate | Antec 750 Watt GamerSeries
Intel Core i3 3220 | Galaxy GTX 650 | 8 GB Corsair Vengeance | ASrock B75M | Samsung 840 120GB