This KVM is perfect for old system like this. The only problem I had, was that the ps-2 universal mouse won't work with the 386 pc's serial port. I'm pretty sure it is the adapter's fault. So although the KVM would switch a ps-2 mouse, I have to have both mice available depending on the PC in use. To switch from one to the other, use <scroll lock> <scroll lock> 1 (or) 2. You can also use the KVM buttons to switch manually. Although I use the keyboard method. Both of these PC's: a Gateway 2000 Intel-486 @66mhz and an Acer clone AMD-386 @40mhz are connected to the home network by ethernet and therefore can exchange files easily using the KVM switch. The keyboard is the Gateway 2000 Anykey programmable keyboard, so the keyboard KVM command can be programmed as a single key press.