BIOS Support for 5.25-Inch Diskettes

This Field Change Order (FCO) details the required BIOS update (version 1.22, P/N 23-397E9-00) for specific DECpc computer models (736, 741, 743, 744, and 746) that require support for 5.25-inch 360KB diskettes. It addresses several issues, including reading 360KB diskettes, disk type compliance for certain Quantum drives, extended printer support, and display sync polarity in 1024x768 mode. The document provides detailed step-by-step instructions for site preparation using ESD safety precautions, removing the chassis cover, identifying and replacing the BIOS ROM chip on the Main Logic Board, and verifying the upgrade upon reboot.