Dos--Notes

Must install HIMEM.SYS for dos=umb or dos=high.

You must install the HIMEM.SYS device driver before you specify either dos=umb or dos=high.

Using the UMB parameter

You must specify the dos=umb command in order to load programs and device drivers into the upper memory area. Using the upper memory area frees more space in conventional memory for programs. In addition to using this command, you must install an upper-memory-block (UMB) provider.

Using the high parameter

If you specify the high parameter, the MS-DOS subsystem attempts to load part of itself into the HMA. Loading part of MS-DOS into the HMA frees conventional memory for programs.

Combining parameters

You can include more than one parameter on a single dos command line, using commas to separate them. For example, the following command lines are valid:

dos=umb,low
dos=high,umb

You can place the dos command anywhere in your CONFIG.NT or equivalent startup file.

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