AutoCAD-based products require at least 2 GB of physical memory (RAM) for working
with 2D drawings, and 4 GB is recommended for working with 3D models.

The size and complexity of a model often defines how efficiently an application runs.
If you notice increased hard drive activity, it means that physical memory has been
exceeded and data is being passed to a swap file (virtual memory).

A swap file is an area on the hard drive that the operating system uses as if it
were physical memory (RAM). The swap file size is basically a limit which restricts
the total virtual size of the AutoCAD process. A good rule of thumb for configuring
your swap file is three times the amount of physical memory on your system. This usually
sets the limit high enough to prevent running out of swap space. Refer to the Help
and Support information for your operating system about installed physical memory
and for allocating disk space for virtual memory.

Graphics cache files are created and maintained to optimize performance and increase
the regeneration speed of objects with complex geometry such as 3D solids, non-mesh
surfaces, and regions. These cache files persist between drawing sessions and are
saved in your . . .AppDataLocalAutodesk. . . folder under GraphicsCache. The maximum
number of graphics cache files that are maintained is limited in number and total
size by the CACHEMAXFILES and CACHEMAXTOTALSIZE system variables. If the limits are
exceeded, the oldest cache files are automatically deleted.