Question Daisy-chaining monitors to KVM switch ?

daufoi

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I have two Dell U2414H monitors that are daisy chained via display port 1.2. Now that I am working from home, I would like to connect these monitors to both my home pc and work laptop. Work was kind enough to buy me a display port KVM switch but then the laptop only has HDMI input, no display port. I tried purchasing a DisplayPort to HDMI cable but it didn't work. After returning it, I noticed it says uni-directional on it. Do I need to get a bi-directional cable in order to make this work? Or does this simply not work? The bi-directional cables are a bit more expensive and I would hate to make another purchase just to have to return it again.
 
As far as I know. You need a DisplayPort 1.2 for daisy chaining (MST). HDMI doesn’t support it.

Does your laptop have USB C or Thunderbolt? Check if any of those ports also allows DisplayPort.

From what I can find. The only alternative a DisplayLink DL-6950 only supports DP SST on each individual port. Even though the DL-6950 sports dual monitors. Each DP is only SST.
 

daufoi

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It does have a thunderbolt port! Would that work to connect the monitor?

I also found an HDMI to DP cable (not DP to HDMI). But it's twice as expensive ($32).
 
It does have a thunderbolt port! Would that work to connect the monitor?

I also found an HDMI to DP cable (not DP to HDMI). But it's twice as expensive ($32).

HDMI to DP won’t work. As far as I’m aware. As the HDMI output simply doesn’t support MST.

The Thunderbolt port will probably work. They normally have DisplayPort output and usually support MST. Except for Macs. But that is more a macOS issue. As I recall the Intel Macs supported MST when booted to Windows.

So get a USB C to DP cable. It needs to be at least a DP 1.2 cable. To use the Thunderbolt port. You only need a true Thunderbolt cable for Thunderbolt devices and docks.

Edit: I'm assuming your laptop is a newer one with Thunderbolt 3 or 4 to use USB C. As non Apple Laptops with Thunderbolt 1 or 2 are as rare as hens teeth. But those older standards would use mini DP to DP.
 

daufoi

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HDMI to DP won’t work. As far as I’m aware. As the HDMI output simply doesn’t support MST.

The Thunderbolt port will probably work. They normally have DisplayPort output and usually support MST. Except for Macs. But that is more a macOS issue. As I recall the Intel Macs supported MST when booted to Windows.

So get a USB C to DP cable. It needs to be at least a DP 1.2 cable. To use the Thunderbolt port. You only need a true Thunderbolt cable for Thunderbolt devices and docks.

Edit: I'm assuming your laptop is a newer one with Thunderbolt 3 or 4 to use USB C. As non Apple Laptops with Thunderbolt 1 or 2 are as rare as hens teeth. But those older standards would use mini DP to DP.

I got the necessary cable and the monitors and mouse both work! Now the keyboard is not working! Both my mouse and keyboard are not on the device's list of compatible keyboards and mice. I was thinking maybe if I upgrade the firmware but the instructions are in gimmerish. It says the hotkeys to invoke upgrade mode are [Scroll Lock], [Scroll Lock] [p] [g] [r] [a] [d] [e] [Enter] . I tried a number of things and didn't work. This might be hopeless. :(

Do you know what I'm supposed to press when the keys are written like that?
 
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