Monitor resolution problem on a KVM Switch Dock

[BMorto]

Hi,

Hoping to find some help with my pc setup, I've recently changed docking station to a KVM Switch but I'm having a lot of issues with my monitor setup.

• The first issue is that the resolution is limited to 1920x1080 at 60hz when I'm switched to my laptop but in my previous docking station it was much higher.
• The second issue I have was just trying to have arrange them so that I have screen 2 and 3 extended and laptop (screen 1) disconnected but that was a lot of trouble trying getting this to work because it was just defaulting to duplicate screen 1 and 3 or 1 and 2 and then when I changed it, the display settings would minimize and I couldn't open them to keep changes.
• Final issue is that now I have screens 2 and 3 extended they keep disconnecting and reconnecting every now and again.

I have tried changing the refresh rate and enabling and disabling HDR but to no effect. Both monitors are using HDMI cables, I switched HDMI cables to see if this was the issue but it wasn't.

Finally when I switch to my PC, everything seems fine and my resolution is 3840x2160 @ 60hz. Both laptop and PC are using Windows 11.

Hardware
KVM Switch Dual Monitor iDock C10
BenQ PD2705U - 8k HDMI (Identity screen 3)
Gigabyte M32UC - 4k DMI (Identity screen 2)

I don't know enough about computers to understand what the issue could be, so I'm hoping someone here knows what is going on.

Oh and just to make it more trickier, my laptop is a work laptop and most of the settings are locked down and not accessible.

Thanks,

 

[Nitefly]

First thing first, try disabling the ‘auto-detect’ setting on the monitors and see if that stabilises some of the minor issues re: screens disconnecting. The monitor might be auto-detecting it’s connected to your PC, for example.

You’ll want to check the data bandwidth limitations of the hubs. It might be lower than the bandwidth of the hdmi cable. If you can plug your work laptop directly into the monitor via HDMI and get a higher refresh rate than via the hub, this is probably the issue. Likewise, how is your docking station getting audio visual signal? If it’s not via hdmi than this suggests the same.

 

[BMorto]

So the laptop is connected to the hub only by USC C but desktop is connected via USB-A and HDMI to hub.

I tried using just 1 monitor through the hub which resolved the resolution situation and I reduced the refresh rate from 60hz to 23hz and this helped with the disconnecting for about and hour and now it's gone back to d/c like every few seconds. I am also going to try and get some HDMI to DP cables, because I read that HDMI don't support duel monitors?

Odd thing is it all works perfectly via my PC, my theory is that maybe it just can't handle the connections via the USB C cable on the laptop?

 

[cokecan]

Most KVM's don't have EDID emulation built in unless spending many hundreds on something dedicated (TESmart, Level1Tech, ConnectPro etc), which means as soon as you switch input, the other device(s) connected to the non-active input(s) can't see any monitors connected. The equivalent of just disconnecting a monitor cable, and so things like window position are forgotten and in the case of many laptops with the lid closed may trigger sleep/standby. EDIT; just seen this KVM might actually support EDID emulation!

What was the previous docking station you had and what laptop do you have? Does the laptop support just usb-c or is it a thunderbolt 3 or 4 connection instead (likewise with the old dock)?

 

[BMorto]

Hi, my first docking station was a BenQ becreatus which was used with the same monitor/laptop and worked fine for both monitors. I'm not sure what thunderbolt connection my laptop has but it is a thunderbolt connection, it's probably 3.

I've ordered a new USB C cable with a higher data speed and some 8k DP to HDMI cables to see to connect monitors to Dock in this method. (Dock only has HDMI outputs)

https://www.amazon.co.uk/BenQ-beCreatus-monitors-Charging-DP1310-Gray/dp/B0CB5CRZ5T​