Go ahead and pat yourself on the back if you waited this long to upgrade your graphics card, you now have a bunch of next generation parts to choose from, including dual-GPU cards from both AMD and Nvidia. These two heavyweights aren't finished, either. According to reports, AMD is working on a mid-range Radeon HD 6790 videocard built around the 40nm Barts GPU. It should end up faster than the Juniper-based HD 5700, and perhaps nearly as fast as the 6800 series.
According to news and rumor site Fudzilla , the HD 6790 will sport 800 stream processors organized in 10 streaming multiprocessor units. That means there will be two blocks of 400 stream processors with a dispatch processor for each block. That's the same number as found in the HD 5770 (800 SPs), but with a different arrangement.
Other expected features and specs include 32 ROPs, 40 TMUs, and a 256-bit memory bus. Clockspeeds and amount of memory are both up in the air, though early rumors have the GPU pegged at 840MHz and the memory at 1050MHz (4.2GHz effective).
Look for the HD 6790 to compete with Nvidia's GTX 550 Ti, both in performance and price. Expected release date is April 5th.