for the high end of your price range...
MSI 6800GT 399.99' ">http://www2.newegg.com/Product...p?Item=N82E16814127140
Powercolor X800XL $339' ">http://www2.newegg.com/Product...p?Item=N82E16814131303
there are cheaper 6800GTs out there, btw...and for the low end of your price range, look no further down the food chain than a 6600GT, 6800 vanilla (12 pipelines), or an X800.
although, considering you're using a 9200...a 9600XT or even a 5700Ultra would be quite an improvement...
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