Where DLSS 3 interpolates one frame between two rendered frames, MFG can generate one, two, or three frames. Nvidia calls this MFG 2X, 3X, and 4X modes, with the last being “up to twice as fast” as 2X framegen. A factor in making MFG work is that the AI network needs to run faster than before.
Plenty of games with DLSS 3 support seemed to hit a bottleneck with the OFA fixed function hardware, yielding less than stellar improvements in frame rates. My experience with DLLS 3 is that you want it to give at least a 50 percent boost to frame rates, with 80 percent or more desirable. If it only manages a 30–40 percent, it typically ends up feeling worse than non-framegen performance.