MICRODEM requires  the DEM be in memory (RAM) because:

Running out of  memory can come from two sources.  You should be able to tell which source caused the problem by looking at the error message.  If it does not include words like "DEM", "column", or "Row", it is probably being passed from the operating system to MICRODEM, and it is unlikely we can fix the problem and you will have to be less "greedy" and "smarter" in what you want to do.

With the 64 bit version the only one normally supported, and even larger DEMs could be moved into memory.

Last revision 4/4/2018