Upper Memory Block [LIM] [AST
DOS: Upper Memory Block (640K to 1Mb).
Upper Memory Block A specific area of the main memory. UMB is a blank memory area of UMA in the MS-DOS environment where device drivers and memory-resident programs can be assigned, and is part of the XMS standards.
Abbreviation for upper memory block. upper memory area The 384 KB of RAM located between 640 KB and 1 MB. A utility called a memory manager can create UMBs in the upper memory area, in which you can load device drivers and memory-resident programs.
The sub sections of free memory which can be utilized for TSR's between 640KB and 1024KB.
Upper memory blocks. A reserved 384K area of system memory in the range 640K to 1MB. DOS can use it for device drivers, memory-resident programs (TSRs) and ordinary applications.
Abbreviation for upper memory blocks.
The UMB (Upper Memory Band) is the memory range from 640k - 1024k, and is used for DOS device drivers, to free up conventional memory.