Scrl Lk/Scrl Lk/Enter ( or 1,2 ) is usually the command for a two port KVM. I've got a 4 port ( about $50 USD ) and am building a two port into the computer I'm assembling right now. I've seen them go up to 16 port ( for server rooms ) but hear they are terribly expensive. Since Hubby has so many systems, I assume he does that sort of thing proffessionally and probably can get a used one on the cheap. If he doesn't already know this, KVM switches can be stacked as long as the keyboard commands differ. My 4 port will move from PC to PC but once it hits my new computer, I give a different key command and it will switch the new computer internally. Num Lock/Num Lock ( 1,2,3,4 ) will flip it out of the new rig again.