computer freezes when accessing Zip disk

IDE Zip on secondary cable with CDRW as slave or as master (I’ve tried both ways). Motherboard BIOS has been updated and new drivers from Iomega have been loaded for Zip. OS is Win Me. Processor is 800 MHz & computer has 64 MB RAM. If I try to format zip disk, computer freezes. If I try to copy large files, computer freezes. When the CDRW was removed, Zip apparently worked.