AMD plans to launch Radeon HD4890 on Thursday, April 2nd and the card will work some 10+ percent faster than 4870. The chip looks the same with some power optimisations in place but it will share the same transistor number.

We would suggest that we could call RV790 the other revision of R770 chip rather than a brand new design, and call this evolutionary rather than revolutionary product.

It should get ATI some breathing space but Geforce GTX 285 remains the fastest single chip based product while GTX 295 will remain the fastest card around, at least until ATI doesn’t release the real performance 40nm part.