Using EMM386.EXE to Load Drivers into Upper Memory Blocks on MS-DOS
Learn how to free conventional memory on MS‑DOS by loading device drivers into Upper Memory Blocks with EMM386.EXE and HIMEM.SYS.
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msdosFree Conventional Memory in MS-DOS with EMM386 and Upper Memory Blocks
Use EMM386.EXE on 80386+ hardware to create Upper Memory Blocks, move DOS and drivers out of the 640 KB conventional limit, and free memory for DOS applications.
How to Configure Upper Memory Blocks in MS-DOS 5.0–6.22 Using EMM386.EXE
Learn how to free conventional memory in MS-DOS 5.0–6.22 by configuring Upper Memory Blocks with EMM386.EXE, including exact CONFIG.SYS lines, verification steps, and recovery tips.
Change in UMB allocation for DEVICEHIGH drivers when exceeding available upper memory in MS-DOS 6.22
Goal: Identify the rule that MS‑DOS 6.22 uses to decide which DEVICEHIGH‑loaded device drivers remain in upper memory blocks when the total requested UMB space exceeds the amount available from EMM386. Constraints/uncertainty: The placement varies with the order of DEVICEHIGH lines in CONFIG.SYS, the presence of LOADHIGH programs, the dynamic fragmentation o