I am currently running a GeForce 6600GT 128MB. The two card I am looking to upgrade too are a 6800XT 256MB or a 7800GS 256MB. They are about $150 apart. Does the added performance of the 7800GS warrent the price change? Should I dish out the extra money for the 7800? or will the 6800 be somewhat comprable? Also, if I went with the 6800, would I notice a difference from my original card? Any suggestions of comment would help.