You should check the cmos. Quite often the floppy defaults to 1.2 5.25 instead of the 1.44 3.5 disks. If the cmos is correct, hit F1 and let the system boot up. Watch the floppy drive. If the green light stays on, it is usually an indication taht the data cable is backwards. If both are correct, try telling the cmos that there is no floppy drive and see if the system boots. Could be a bad floppy drive.