No, the BIOS finds it as a Zip 250, ATAPI device, but only 250 MB disks will work. It won't read or write to 100 MB disks at all. I took the Zip out and put it in another machine, a 133a chipset and it reads both 250 and 100 MB disks. Put it back in the ASUS and only 250s work. Hmmm.... I should have said this is in Windows 2000 with latest IOMEGA drivers.