Geforce gts 250 or radeon HD 4850?

TechPowerUp's ranking when they tested a Galaxy GeForce GTS 250 1 GB :

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I wouldn't say that chart is entirely fair comparing a GTS 250 1GB to a 4850 512MB rather than a 4850 1GB, but anyway.... it depends on what games you play. I say that of the two go with the 4850. It would be worth it to spend a little more and get something newer like a 5770 though.