Excellent. The submitted file in2war64.com shows only the blue "background" when run from bare-metal booted DOS floppy on a Pentium D (x64 based on dual x86) w

Excellent. The submitted file in2war64.com shows only the blue "background" when run from bare-metal booted DOS floppy on a Pentium D (x64 based on dual x86) with its associated Intel graphics hardware. No sound either. Your file "war" is a nice binary, works natively as sector 0 of a floppy disk, with a traditional FDD plugged directly into the legacy FDD parallel connector. On the same hardware. Also works with USB floppy drive, even on a UEFI PC as long as the Legacy/CSM is enabled and Secure Boot is disabled. To use a common USB Flash Drive (UFD) natively instead of a floppy, legacy BIOS can require a partition table to be also present on sector 0 of the removable UFD. This can be effectively added by partitioning (format not needed) after copying "war" to sector 0 of the UFD: from Linux command line: First copy "war" to sector 0 of the UFD, where X is the identifier of your unmounted UFD: (sudo) dd if=/<path to>/war of=/dev/sdX bs=512 count=1 This overwrites any MBR and partitontable that may already be on sector 0 of the target X UFD; with the functional "war" replacing the MBR, and zeroes replacing the partition table. Only sector 0 is replaced, all other sectors remain unchanged. At this point sector 0 of the UFD is no different from sector 0 of the working floppy disk. Then create a partition on the target X UFD using cfdisk: (sudo) cfdisk /dev/sdX make it primary, full size, bootable, type 0C Only the final portion of sector 0 is altered (leaving the "war" binary intact at the beginning of sector 0), all other sectors remain unchanged. Then the UFD boots natively just like the floppy. Still for UEFI need Legacy/CSM to be enabled and Secure Boot disabled. Still no sound.