I ended up doing a lot of research into why my windows don't stay where I placed them when I switch computers. It turns out that the DisplayPort specification requires sending a monitor-off signal. You absolutely must use HDMI if you don't want this problem. I was able to use other KVM and HDMI DisplayPort cables without any problems. If that's not your main concern, this is a fantastic KVM. It had no trouble moving the 4k and WHD display. Switching was quick, it took me minimal effort to get my gaming keyboard and mouse up and running.
CKL 4 Port KVM Switch Dual Monitor DisplayPort 4K 60Hz: Unprecedented Multi-Computer Control with Audio, USB 2.0 HUBS, and DP 1.2
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Computer case Deepcool Matrexx 55 black
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Computer case be quiet! Pure Base 500 black
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