Monitor not waking up after suspension with USB-C to DisplayPort cable

General Help
1

I have an X670E mainboard with an AMD 9800X3D CPU and my monitors are a Dell G2724D (DisplayPort <-> USB-C to Mainboard) and a U2515H (HDMI
<-> HDMI to Mainboard). Currently I am not using the NVIDIA graphics card, so my both monitors are connected to the mainboard. The BIOS is the most recent version.

I have following problem: When the machine wakes up after suspension, the monitor which is connected via DisplayPort <-> USB-C to Mainboard stays black. As you can see, it is kind of recognized as monitor, but not correctly, as resolution and Hz are wrong:

image
image810×900 37.8 KB

To fix that, I always need to restart the system.

2

Do You have the Possibility to connect it directly to the DisplayPort without the USB-C Adapter? So, You could test if this Adapter makes the Problem.

A Thing independent from this:

Does this run normally with the 6.8 Kernel in Zorin or do You have installed a newer Kernel?

3

It is not an adapter, it is a DisplayPort <-> USB-C cable because the mainboard does use USB-C instead of DisplayPort.

I use Kernel 6.8, I did never change the Kernel:

Linux office-linux 6.8.0-49-generic #49~22.04.1-Ubuntu SMP PREEMPT_DYNAMIC Wed Nov 6 17:42:15 UTC 2 x86_64 x86_64 x86_64 GNU/Linux

1 Like
4

Cable, okay. Did you tested another Cable to see if maybe the Cable is broken? Or do You have the Possibility to connect the Monitor with another HDMI Cable to test if it in common works?

5

The monitor has worked before without any problems on a B760 mainboard where it was a DisplayPort<->DisplayPort cable. I don't think the USB-C cable is defect, because this problem only arises after suspension. If the cable would be defect, I would have flashing/flickering problems. It must have something to do with the AMD GPU.

6

Yes, could be. Or the Problem is that it is a DP>USB-C Cable and the System maybe have Problems with the Signals because it isn't a normal DP Cable.

7

That is by the way the mainboards says:

image
image1215×191 31.4 KB

So the graphics of the mainboard with the AMD 9800X3D are HDMI and 2 x USB4, which name does not contain a space in it (see 'USB 3.2' instead). And it is the successor of Thunderbolt 3 or is based on it. And seems to use USB-C as mechanical socket. To be honest I don't understand this, we now have a billion different socket types and one trillion specifications, so I really don't know what all that is, but it seems to be the cause for this problem.

8

Okay, so Your Graphics Output is not running over Your Nvidia Graphic like You wrote at Your first Comment. So, it should come from the built-in AMD Graphics from the CPU.

Well, this Graphics is pretty limited. And On Your Picture stands'' VGA resolution support depends an processors' or graphics cards' resolution.''

I would think now, that the built-in Graphics is simply not able for handling both Displays. Maybe with a normal APU what AMD offers (f.e. 8600G) bue with this ''small'' integrated Graphics ...

When You use Your Nvidia Graphics: Does this works without Issues or do You have the same Problems?

9

Thanks for your answer :slight_smile: I think you misread, in my first comment I wrote that I would not be using the NVIDIA graphics card.

I would be very surprised if two monitors would be a problem for a modern CPU such as the 9800X3D. Also the CPU is in fact capable of handling both monitors, I have no performance issues.

The problem was not present on the graphics card when I used it before.

10

Since it is not that expensive, I ordered a DisplayPort<->USB-C cable from a different manufacturer to test it with that.

11

The Thing with the CPU is: there are only 2 Graphic Core's on it. What You could try: Unplug Your HDMI-Monitor and only use the DP>USB-C Monitor and look how it behaves. I mean: can You adjust Resolution and Refresh Rate and does it stay on it. If this should work alone, plug in the HDMI-Monitor again and look if it is stable in Usage.

1 Like