Review on CKL HDMI KVM Switch 2 Port Dual Monitor 4K 60Hz with Audio, 2x2 PC Monitor Keyboard Mouse Selector and 2 USB 2.0 HUB (Model: CKL-922HUA-2) by Jim Diaz

Thing doesn't work for 2 4k monitors. Only one of them even turned on and only appeared during computer startup. Screen goes black when logging in. The other monitor uses a Displayport to HDMI converter to connect the computer to the KVM (a very common scenario since most graphics cards only have an HDMI port). This ad doesn't work at all. My second computer (laptop) cannot recognize a display. It works great with USB stuff, but for the price this thing should just work. Very very disappointed.