ATEN US224 2 x 4 Port USB 2.0 Peripheral Sharing Switch, USB 2.0 Compliant, Support For Windows, Linux, Mac & Sun, Overcurrent protection, Hot pluggable, LED indicators, Remote Port Selector

This product works flawlessly for me. It has advanced features (such as being able to disable keyboard/mouse virtualisation), up-to-date specs (e.g. 4K 60Hz, displayport MST compatible, USB 3) and includes all the cables necessary in the box (which are guaranteed to work, third party cables are a lottery with *any* device).

I had high hopes when I bought this - as a consultant I'm constantly juggling different machines and keyboards linked to my 34" monitor. This is the first 4k KVM 4-port switch capable of delivering 3440x1440 that I've seen, so was really pleased so be able to declutter the desk and have one mouse and keyboard to drive all the laptops / desktops.Unfortunately, I found the switch introduced irritating lag to both keyboard (Microsoft wireless 5000) and mouse (Logitch 325 wireless), and I'd spend 10 to 30 seconds waiting for the system to 'catch up'. This was not only when first switching to a different machine but seemed to occur at random intervals, more frequenty when I was on a VPN connection or using a browser window though not exclusively in these situations.Despite a long email conversation with theAten helpdesk and trying a number of setting changes, the problem persisted, so the unit went back to Amazon after a week of frustration. Thanks to Amazon for refunding the purchace.

Use this to switch between four devices (1 server, 2 laptops and a test device, commonly a Pi). Had it for nearly 3 years now and still going strong Switching works from keyboard - make sure you get a keyboard with a Scroll Lock key or it's a pain - although it auto-switches if a device is powered off.Only problems I have had have been:o Cheap monitors not switching back on without being power cycled when switching. Went away with a better monitor, so not really the device!o You can't skimp on cables, especially if long. One of mine is 4m and works fine - but it took a good quality braided cable to do soo Occasionally get detection problems with the USB - again, probably my device rather than this box, but resetting the KVM always seems to fixo It does NOT emulate screen and any USB devices when it switches - your device will see the screen as disconnected and reset its resolution. For me, not a big problem, but it does mean for some configs you have to wait for screen re-detection.o It doesn't get on with all HDMI->DP converters; some work, some don't. I found USB powered ones worked okay for the one device I have that isn't DP.Original firmware was a bit buggy but current update (came out in about 2018) works fine.

If you want to use anything other than the 1.5m DisplayPort cables Aten provide - be prepared for a whole world of pain. I've wasted numerous days testing this KVM with various monitors, operating systems and graphics cards to find that the CS1924 does NOT support the standard for 4K over DisplayPort. All my test hardware works perfectly with various combinations, including 10m Displayport cables. But as soon as you try and use it with the KVM and anything other than Aten's cables (even 3m DisplayPort cables), you won't get 4K and anything else is hit and miss.To make matters worse - Aten only offer support if you are using their cables - otherwise it's "all bets are off".Given the price of this item, it's unacceptable and ultimately makes the product unfit for purpose.If you are able to use the supplied Aten 1.5m DisplayPort cables in the box to connect your machines, then this KVM will probably be okay, but even then I've had issues with display noise and flickering on a couple of my machines. Unfortunately (at the time of writing) there is no other alternative - but I would suggest you don't bother, than be ripped off by this product.