DOS Specifies that MS-DOS should maintain a link to the upper memory area, load part of itself into the high memory area (HMA), or both. You can use this command only in your CONFIG.SYS file. Syntax DOS=HIGH|LOW[,UMB|,NOUMB] DOS=[HIGH,|LOW,]UMB|NOUMB Parameters UMB|NOUMB Specifies whether MS-DOS should manage upper memory blocks (UMBs) created by a UMB provider such as EMM386.EXE. The UMB parameter specifies that MS-DOS should manage UMBs, if they exist. The NOUMB parameter specifies that MS-DOS should not manage UMBs. The default setting is NOUMB. HIGH|LOW Specifies whether MS-DOS should attempt to load a part of itself into the HMA (HIGH) or keep all of MS-DOS in conventional memory (LOW). The default setting is LOW. Related Commands For information about loading a device driver into the upper memory area, see the command. For information about loading a program into the upper memory area, see the command.