+ 0 Votes Reading 5.25-inch floppies n2add May 29, 2013 at 12:59am PST 1. I purchased a 5.25-inch floppy on eBay and installed it in an old computer and proceeded to copy my 5.25-inch disks. About 20% of the disks could not be read properly. I also did the same thing with my 3.5-inch disks. Everything I could copy is now on a CD.2. I tried one of those dual drives but I could never get it to work properly. I tried various combinations of the jumpers but no luck. 3. Some computers that do have a floppy connector on the motherboard will only recognize 3.5-inch drives.