Trouble with Boot floppy on AMD SC520 motherboard

I have QNX 4.25 and have been booting PC-104 motherboards with an AMD586 - P75 processor for years in order to load system and programs to a “DisK on Chip”. I first use a boot floppy with .Boot image, .inodes, .bitmap and .altboot.
The sysinit file is…Dev & Dev con & tinit -t /dev/con1 &
The bin folder contains Dev, Dev.con, Fsys, Fsys.floppy,login, ls, mount, sh , tinit.
We now have a new motherboard with an AMD SC520 processor.
When I try to boot from the floppy and a VGA card is installed it looks like it is reading it because I see the normal …on the screen but there is no sound from the floppy drive and the dots will go on forever. If I program the chip on the old motherboard and put it in the new one I can read and write from the floppy drive no problem.
Does any one know the problem here ?