 The 5.25" disks were formatted on both sides with five 1024 byte sectors per track with 80 tracks per side for a total of 800K per disk.The standard configurations includes two serial ports, a parallel port, a general purpose external DMA bus (GPED), separate connectors for 5.25" and 8" floppy disk drives, and a hard disk interface.The hard disk interface is either IMI hard disk controller model #7710 or SCSI depending on the motherboard version.