You can use a passive displayport switcher. I have the Alienware 3420DW and just got this (https://www.newegg.com/p/183-0075-00026?Item=9SIAEKBBMV2800). The monitor is DP 1.2 so 120Hz @ 3440p with gsync and it all passes through the switcher without issue. My setup now has a USB 2.0 switcher for keyboard/mouse/headphones and the DP switcher for graphics both ziptied to a display post. That way switching machines is two button presses. Much better than a KVM IMHO that will likely go absolute next monitor upgrade.