Multidisplay and USB type C / Thunderbolt problem

Description of the problem:

When using the multi-display command on a Windows standalone build, with the below script (Unity's example), with three cameras each connected to three different displays, the fourth camera on the main display (laptop). The display connected to USB C display port/Thunderbolt 3 crawls in framerate. This situation is unusable. The other display ports- on HDMI and mini display port work fine. (As you can see I am not setting the resolution just letting it default to native).

My need is to use a laptop, and the majority of new laptops only have the third display output as USB C/Thunderbolt 3 which doesn't work with multidisplay. Please advise on a solution or any/all information regarding this problem. I have to think someone else has experienced this? -thank you -D

using UnityEngine;
using System.Collections;
public class DisplayScript : MonoBehaviour

{

// Use this for initialization

void Start()

{

Debug.Log("displays connected: " + Display.displays.Length);

// Display.displays[0] is the primary, default display and is always ON.

// Check if additional displays are available and activate each.

if (Display.displays.Length > 1)

Display.displays[1].Activate();

if (Display.displays.Length > 2)

Display.displays[2].Activate();

if (Display.displays.Length > 3)

Display.displays[3].Activate();

if (Display.displays.Length > 4)

Display.displays[4].Activate();

}

// Update is called once per frame

void Update()

{


}

}

 

Your issue is most likely hardware related. For example, if your faster displays are connected to a fast nVidia GPU while your USB C displayport is connecting to your significantly slower CPU integrated graphics - which is a common arrangement for laptops as far as 5 minutes of googlefu turned up for me.

So before you test on another laptop, you need to verify what GPU each of the display outputs is connecting to, and if all of them can run on the faster GPU at the same time. Not something generally discussed in a laptop's marketing materials though. A desktop would be a much better solution for this type of thing.