Data type Range Default value
REG_SZ Number in megabytes
Amount of Memory Default Value
< 12 MB 3 MB
12 - 16 MB 6 MB
> 16 MB 8 MB


Determines the amount of virtual memory allocated to a Windows 2000 virtual DOS machine (NTVDM) to run 16-bit Windows applications. This entry is used only on RISC systems. On computers with Intelâ„¢ processors, the system calculates this value based on the amount of physical memory on the computer.

For each megabyte of memory specified in wowsize, the system allocates 1.25 MB to the NTVDM process. For example, if the value of wowsize is 4, the system allocates 5 MB of memory to the NTVDM process.

Caution Image Caution

Do not set wowsize to less than 3 MB. Most applications cannot run in an NTVDM with less memory.