ATi Rage Fury MAXX is a dual processor graphics card based on the ATi Rage128 PRO. Although there are 64 megabytes of SDRAM, it is effectively a 32 megabyte board as each graphics processor uses a discrete pool of video memory that is evenly distributed between the two processors. There is also a Programmable Logic Device (PLD), labeled in the board diagram, that switches between two CRT controller application-specific integrated circuits (ASIC) to enable Alternate Frame Rendering (AFR).
By the use of Alternate Frame Rendering (AFR), whereby each processor renders alternate frames separately and in parallel, a near doubling of peak memory bandwidth and polygon throughput is possible. However, if one processor is stalled while the rendering of the succeeding frame in the other processor proceeds smoothly and in parallel, a situation can arise whereby one frame takes a longer time to be displayed, followed, in rapid succession, by the display of the next frame. This leads to the perception of uneven framerates.
This effect is illustrated in the underlying graph, which shows the frames per second (FPS) recorded using the Graphics Performance Toolkit for 200 frames (frames 601 to 800) during a run of the 'Quake III: Arena' timedemo. The uneven framerates of MAXX, as the underlying graph shows, manifest as jerky animations that are particularly marked at high resolutions. The smoother framerate graph of GeForce DDR, at corresponding frames, is shown for comparison.