This particular model only works when the computer is OFF at 30Hz. This mode hasn't been present on modern GPUs for more than half a century. Also, the Displayport implementation doesn't allow customization for HDMI input or output, so most computers just can't work with it. I ended up upgrading to GCS1934m which is slightly better.
4 Port USB 3.0 Switch Selector - Pubioh KVM Switch for Mouse, Keyboard, Printer, Scanner - 2 in 4 Out Sharing Box with Switch Button and 2 USB 3.0 A to A Cables
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Enhance Productivity with CKL HDMI KVM 2 Port 4K 30Hz Dual Monitor Extended Display (CKL-922HUA)
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🔌 HDMI 2.0 4 Port KVM Switch with 4K@60Hz, 2K@144Hz,1080P@120Hz Support, 18Gbps Bandwidth, USB 2.0 Keyboard/Mouse/Printer/Monitor/PC Selector, Audio Out/Mic In, HDR10, Dolby Vision, Dolby/DTS, HDCP2.2 Compatibility
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NEWCARE HDMI KVM Switch: 4K@60Hz, 2x1 HDMI2.0 Ports + 3X USB KVM Ports - Share 2 Computers on UHD Monitor, with Wireless Keyboard and Mouse Support - USB Disk, Printer, USB Camera Compatible
10 Review