The RV770 is manufactured on a 55nm manufacturing process as was the Radeon 3000 series and the 4870 sports about 965 million transistors. The card doesn't add much in way of new features from the 3870 still supporting DX 10.1, CSAA, Crossfire, and more although one new addition is the inclusion of the next-gen video decoder, the UVD2. The 4870 sports a 750MHz core speed from the 625MHz of the 4850, it still boasts 512MB of RAM but this time it's super high bandwidth GDDR5 as opposed to GDDR3 which it uses to over come the 256-bit memory interface. The 4870 has a 160W TDP and requires two 6-pin PCI-Express connectors in order to function and thus with SLI you'll need 4 6-pin PCI-E power adapters so keep in mind if you do go for this card. It is also dual slot and doesn't get quite as hot as the Radeon HD 4850 but definitely gets up there. Perhaps most impressive of the 4000 series is that the number of stream processors has bolted to 800 from 320 from the 3000 and 2000 series more than doubling overall and allowing for huge gains.



Link: AMDZone