New and sealed. Serial numbers scratched off (see pics). The Microsoft MS-DOS 5 Upgrade on a 5.25" floppy disk is a vintage operating system designed for DOS-compatible computers. This upgrade version requires a minimum of 512 KB of RAM and a processor speed of 8086/8088 or higher. With a minimum hard drive space of less than 50 MB, this operating system is compact and efficient for its time. The English-language software comes in a single 5.25" floppy disc, making it a unique and nostalgic piece for collectors or vintage computer enthusiasts.
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