The PC30-III has a PC40-III motherboard and is a 286 running at 12MHz. I have a 1.2M 5 1/4" (Drive 0) floppy installed and a 1.44M 3 1/2" floppy (Drive 1). The drives were confirmed working in a 486 based system and are recognized when installed in the Commodore PC30. The 486 will boot from the 5 1/4" drive with a DOS 3.1 and a DOS 6 boot disk. Transferring them into the PC30 and I get a "Disk Boot error" using the same boot disks. I have tried installing the 5 1/4 only in the PC30 but still get the same boot error. I tried the 3 1/2 only with a good boot disk - same result. I've changed the floppy cable and even installed the ISA floppy controller from the 486 system - no joy. I've even tried a 360K 5 1/4 and a 720K 3 1/2 drive in the system. I don't have a hard drive that meets the BIOS drive table settings on the PC30 or I would set up a bootable hard drive in another system and transfer it to the PC30 just to verify the system will boot to DOS. This one has me baffled.