A set of presentation slides have leaked today at VR-Zone that indicate AMD is developing a new video chipset to outperform NVIDIA's mid-range offerings at a budget price. The Radeon HD 4830 would sit just below the 4850 by keeping the 256-bit memory bus but carrying 640 stream (effect and geometry) processors versus the 800 of faster Radeon HD cards. It would also carry slightly slower GDDR3 gr
