The 9600GT is loads better than your 7900GT and can be found for around $150 with and without rebates (depending on the specific card). The 8800GS is also faster and can be found for as low as $100 after rebates. Heck, on some newer games even the $80AR 8600GTS is better than the 7900GT. On the ATI side you have the HD 3850 512 also for around $150 and the sub 90$ HD 3650 GDDR3 would also beat it in certain newer games.