Using DEVICEHIGH in CONFIG.SYS to Load Drivers into Upper Memory
Learn how to use the DEVICEHIGH directive in CONFIG.SYS to load device drivers into the Upper Memory Area, freeing conventional memory for DOS programs.
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msdosDEVICEHIGH vs LOADHIGH: Which Approach Maximizes Conventional Memory for DOS Games?
When running DOS games or legacy applications that require at least 50 KB of conventional memory, the decision between using DEVICEHIGH in CONFIG.SYS and LOADHIGH in AUTOEXEC.BAT becomes critical. Both directives aim to relocate code into Upper Memory Blocks (UMBs) when HIMEM.SYS and an UMB provider such as EMM386.EXE are present, but they differ in ordering
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