AMD To Launch Radeon HD4890 "RV790" In April

[largon]

I wouldnt be surprised if ATI actually had even lower running clocks on the RV790XT, like 725MHz or so. Notice how the 3870 ran at 775MHz and the 4870 runs at only 750MHz?

Eh?
HD3870 (RV670) was made on 55GT (high performance process) and it ran a high freq, HD4850 (RV770) is made on 55GP (general purpose, normal performance process), then how does it make sense that RV790 made also on 55GT would run slower than 55GP RV770?