Installing 2nd Floppy on unsupported motherboard Part 1 - Editing the CMOS RAM

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Published on April 5, 2009 12:00:00 AM ● Video Link: https://www.youtube.com/watch?v=z9YXyfG0Vf0

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NOTE: This trick does not work on UEFI based systems. On such systems, the CMOS RAM is virtualized and any changes made in the program shown here will be lost on reboot.
Most motherboards today only have the ability to set-up one floppy drive in their CMOS setup. However, by modifying three or four bytes in the CMOS RAM, it is possible to add a second floppy drive.
Please not that the program shown here will only run on 32-bit versions of Windows and MUST be run as administrator on NT-based versions.
For Vista or newer, right click ACE.exe and select Run as Administrator, or launch from an elevated Command Prompt.
The memory locations shown here are standard IBM PC CMOS locations.
0x10h - Floppy drive types, bits 0-3 second floppy, 4-7 first floppy. 0100 for 1.44MB 3.5", 0010 for 1.2MB 5.25", etc.
0x14h - Installed equipment, set bit 6 to 1 for two floppies.
0x2E and 0x2F - CMOS checksum. Sum of bytes 0x10 to 0x2D. Add what you added to any bytes edited.
The checksum is "big endian" meaning the LEAST SIGNIFICANT bits are on the second byte. Carry over to the first byte if necessary.
If you make any mistake, you will get an error on reboot and your CMOS will be reset to default values.