We all know that desktop KVM is generally an unreliable technology, but it's more reliable than most. I have a 2017 Macbook Pro, a Windows 10 desktop, a 27" Dell 4k monitor and various peripherals. In general, I can successfully switch back and forth. Macbooks sometimes have trouble feeding video to a Dell monitor, but I think it's a displayport issue in recent versions of OSX and I was able to get it working mainly by updating the displayport driver (if you're having trouble with the laptop trying this). Switch to dual displays but the display stays idle, google "os x displayport driver update". I bought this to replace another Siig KVM that I found mostly unusable. Maybe it's just a comparison, but I'm very happy with it.
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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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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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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Fractal Design Define R5 - ATX Mid Tower Computer Case - High Airflow and Silent Optimized - Includes 2x Dynamix GP-14 140mm Silent Fans - Water-Cooling Ready - Black
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Computer case be quiet! Pure Base 500 black
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