How much GPU memory is needed for 3ds Max iray rendering?
The entire scene must fit into GPU graphics memory in order for iray to take advantage of GPU acceleration. If the scene does not fit unto into a GPU’s memory, that GPU is ignored and all processing takes place on the CPU and in RAM and run much more slowly. If the scene exceeds RAM, then iray will use virtual memory and run more slowly yet. For estimating memory usage, budget about 1 GB per 8 million triangles, to which you must also add 3 bytes/pixel for any referenced bitmaps.
