CAD tip # 5989:

Since version 2007 you can limit the amount of this consumed memory through the variables RASTERPERCENT and RASTERTHRESHOLD. On the other hand, too low values (settings) of these variables can inadverently block plotting of larger drawings (maps).

The RASTERTHRESHOLD variable (by default: 20MB) controls the threshold of raster memory in megabytes. If the plotted raster image exceeds the limit, the availability of system memory is checked and the plot is aborted if the image is too big for the available memory.

The RASTERPERCENT variable (by default: 20%) sets the maximum percent of the available virtual memory which can be reserved for raster image plotting.