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Unlocking More RAM in MS‑DOS: How HIMEM.SYS and XMS Break the 640 KB Barrier
MS‑DOS limits programs to 640 KB of conventional memory. By loading HIMEM.SYS and using the XMS interface you can access memory above 1 MB, enabling larger applications and better multitasking. This guide walks through the configuration, usage, and trade‑offs of XMS in a real‑world example.
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