yes they do, as matter of fact in the last week i have work on four different system that use simm edo. the fastess was my son's teacher that had a packard bell PII 233 ,win 95os2 support of 8gig drive and usb ports , we added four 32md edo from compusa at a great price 19.95 and it work out great she was have problems with new 10x8x24 burner underrun errors due to memory. now running win98 2nd plus 128mb edo