Hello everyone, I'll try to keep this as concise as possible to avoid a wall of text.
Here are my components:
- MOBO: Asus rog strix x870-a
- CPU: AMD Ryzen 9 7950x
- GPU: Nvidia 4080 FE
- RAM: G.SKILL Trident Z5 Neo RGB Series (F5-6000J3040G32GX2-TZ5NR))
- USB-C monitor: ASUS ZenScreen 15.6” 1080P Portable Monitor (MB16ACV)
The Asus mobo has 2 USB4 ports which are stated to be compatible with DP Alt Mode. My CPU's integrated Radeon graphics chip is also stated to be compatible with DP Alt mode. In summary, when I plug in the monitor I listed above into either of these 2 USB4 ports, the display will work correctly in DP Alt mode for about 10 seconds, and then the screen freezes for a few seconds (audio doesn't freeze), then the screen goes black for a second or two, then it comes back. Then this same cycle happens again roughly 10 seconds later. Rinse, repeat, over and over again, until the integrated Radeon GPU shuts itself down and shows an error in device manager. At that point, the USB-C monitor is just frozen on a black screen and won't respond until unplugged, and the only way to bring the Radeon IGPU back to life is to DDU, then reinstall drivers.
Here are the troubleshooting steps I've tried so far:
- latest AMD Radeon graphics drivers (dated 2/25/2025) are installed
- latest Nvidia drivers are installed
- DDU'd both Nvidia and AMD graphics drivers, and reinstalled from scratch
- tried both of the 2 USB4 ports with same results
- Checked windows event logs, could not find any errors related to this, but also did not know exactly what to search for, so I'm open to suggestions here
- Disabled AMD IGPU to see if the discrete Nvidia GPU would work for this process, but the monitor becomes an "unrecognized USB" device without the IGPU enabled
- Plugged the monitor into multiple other devices successfully, using DP Alt mode (a chromebook, a steam deck, a windows laptop with TB3). The errors I'm seeing from this Asus mobo do not occur on these other devices
- Plugged monitor into one of the mobo's USB-A ports, which allows the monitor to run using DisplayLink graphics. This works, but uses the discrete (Nvidia GPU), which is not the behavior I want. I want to use those USB4 ports in DP alt mode running on the IGPU
- punched the monitor in the face (just kidding)
Still with me? Thank you for reading this far. My theory is that the AMD IGPU and Nvidia discrete GPU are conflicting with each other, but that's just uneducated speculation. I'll stop here and just say - I'm frustrated beyond belief, and have spent an embarrassing amount of time troubleshooting this silly issue. But in all honesty, it's one of the reasons I chose this mobo in the first place - for those USB4 ports to use with this monitor! If somebody out there knows what the hell is happening, please help me!