I ended up doing a lot of research into why my windows won't stay where I put 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
11 Review
π 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
π TRENDnet TK-803R: 8-Port Rack Mount KVM Switch with VGA & USB Connection, USB/PS2 Support, Device Monitoring, Auto Scan - Control 8 Computers/Servers
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Computer case Deepcool Matrexx 55 MESH black
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Computer case Deepcool Matrexx 55 black
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Fractal Design Node 304 - Black - Mini Cube Compact Computer Case - Small Form Factor - Mini ITX β mITX - Enhanced Airflow - Modular Interior - Includes 3x Fractal Design Silent R2 120mm Fans - USB 3.0
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MasterBox Q300L Micro-ATX Tower with Magnetic Dust Filter, Acrylic Side Panel, Adjustable I/O & Ventilated Airflow, in Black
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