Quirky behaviour with the Steam Deck Dock Display Port port and KVM

Level1 Store KVM Helpdesk
1

KVM Model:

1.4 Display Port KVM Switch - Single Monitor - Four Computer

USB Interface (5-gigabit or 10-gigbit):

10-gigabit

Problem:

Steam Deck works funny.

In the “Normal/Gamescope mode” of Steam Deck:

  • Attaching the Display Port 1.4 → flickers/doesn’t work.
    • Pressing Ctrl+Alt+F4 goes to Terminal 4 properly but cannot rerender the default “F1” terminal
  • Attaching a Club 3D HDMI Input to Display Port Output converter → KVM works normally

In the “KDE Desktop mode”":

  • Triggering Big Picture Mode on Desktop Mode Steam just after attaching the cable “fixes” the Display
  • I cannot return to a working Steam Deck Normal/Gamescope mode after switching to other machines.

Does the official Valve Steam Deck Dock adhere to proper DP 1.4?

2

@wendell do you have any insight?

Do the other PCs via DP 1.4 work fine?

3

Yes its just the Steam Deck Dock. I have a Moshi USB-C to DP 1.4 and it doesn’t seem to work directly on the Steam Deck, at least right now either in normal mode or desktop mode though I swear I remember it used to work.

4

Hmmmmm… does a power cycle affect anything?

5

It did not.