Question Monitor does not output 100Hz over USB-C?

[claustrophobist]

I have this Philips 349P7FUBEB ultra-wide monitor (product link here). It supports 100 Hz (102+ Hz with OC) at its max resolution (3440x1440 WQHD). It also supports AMD FreeSync. I know it does, because when connected to my Desktop PC over Displayport, I have the option of 100 Hz at max resolution, with FreeSync enabled. My Desktop PC has an AMD 5900X and an Nvidia (Aorus) 3080 with 64 GB RAM.

I also have a mobile x86 handheld computer made by Ayaneo. It is the Ayaneo Flip DS (product link here). It has the AMD 8840U APU and 64GB RAM. It supports video-out over USB-C. When connecting another 144 Hz monitor over USB-C (specifically, the Arzopa 16.1 (1920x1080 HD - product link here), the handheld outputs 144 Hz at Full HD without any problems. However, when connected to the Philips monitor, I only get the option of 60 Hz. I even tried lowering the resolution to Full HD (1920x1080) in case it is a USB-C cable bandwidth problem, which of course should not be the case, if it can output at 144 Hz @ FHD. But the option of 100 Hz does not become available. What is more, FreeSync also does not report as being available on the AMD Driver software.

I used CRU to check, and sure enough the tool told me what I suspected: the monitor's driver does not seem to include 100 Hz at any of the expected resolutions (ironically enough, it seems to support it at 640x480 (!)). The monitor's drivers have been updated to the latest one's available on the Philips website. I tried copying (exporting) the settings from my desktop using CRU, over to the handheld. After doing this, I do get the option of 100 Hz at 3440x1440 and at FHD. However, if I try to actually set it to 100 Hz I get a black screen and after a few seconds it reverts back to 60 Hz. Even at FHD, 100 Hz will not work!

I have tried multiple cables, just in case, including the one that is known to output 144 Hz at FHD using the Arzopa 16.1 monitor. I am at my wit's end! What could be causing this?

 

[Glenwing]

I have this Philips 349P7FUBEB ultra-wide monitor (product link here). It supports 100 Hz (102+ Hz with OC) at its max resolution (3440x1440 WQHD). It also supports AMD FreeSync. I know it does, because when connected to my Desktop PC over Displayport, I have the option of 100 Hz at max resolution, with FreeSync enabled. My Desktop PC has an AMD 5900X and an Nvidia (Aorus) 3080 with 64 GB RAM.

I also have a mobile x86 handheld computer made by Ayaneo. It is the Ayaneo Flip DS (product link here). It has the AMD 8840U APU and 64GB RAM. It supports video-out over USB-C. When connecting another 144 Hz monitor over USB-C (specifically, the Arzopa 16.1 (1920x1080 HD - product link here), the handheld outputs 144 Hz at Full HD without any problems. However, when connected to the Philips monitor, I only get the option of 60 Hz. I even tried lowering the resolution to Full HD (1920x1080) in case it is a USB-C cable bandwidth problem, which of course should not be the case, if it can output at 144 Hz @ FHD. But the option of 100 Hz does not become available. What is more, FreeSync also does not report as being available on the AMD Driver software.

I used CRU to check, and sure enough the tool told me what I suspected: the monitor's driver does not seem to include 100 Hz at any of the expected resolutions (ironically enough, it seems to support it at 640x480 (!)). The monitor's drivers have been updated to the latest one's available on the Philips website. I tried copying (exporting) the settings from my desktop using CRU, over to the handheld. After doing this, I do get the option of 100 Hz at 3440x1440 and at FHD. However, if I try to actually set it to 100 Hz I get a black screen and after a few seconds it reverts back to 60 Hz. Even at FHD, 100 Hz will not work!

I have tried multiple cables, just in case, including the one that is known to output 144 Hz at FHD using the Arzopa 16.1 monitor. I am at my wit's end! What could be causing this?

If the USB-C port only has 2 lanes, it will only have half the bandwidth of a normal 4-lane port, which would be enough for 144 Hz at 1920×1080, but only 60 Hz at 3440×1440.