Well 9800 had 8 pipes, x800xt had 16 pipes, r520 has (probably) 32 pipes which = a massive performance increase over cards that are already available. Pci express versions will have crossfire option meaning you can have 2 of the cards linked together to boost performance even more. ([url:af483]http://www.ati.com/products/crossfire/index.html[/url:af483])
If it comes with 32 pipes theres nothing that can touch it for performace with the exception of a 7800gtx sli setup. It supports sm 3.0 for hdr effects and all that crap, and will probably come with improved antialiasing modes to make images more defined. Crossfire setups allow 14x fsaa, when you consider the fact that current ati fsaa max is 6xfsaa and can produce images this clear you have to wonder how smooth 14x would look.
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