CP311-3H External Display Max Resultion

zman1

Hello, just purchased a CP311-3H (MT8183 CPU and Mali-G72 MP3 GPU) Chromebook and am trying to get an external display to  full HD.  I have tried a portable USB-C monitor and hub with HDMI out to multiple displays and the highest resolution is 1440x900.  This is disappointing because the Chromebook has a USB-C 3.2 gen1 port which has the bandwidth capable of full HD @ 60hz.  I have used the same equipment to push full HD from an old Galaxy S8 smartphone.  Does anyone if this is a hardware limitation or hopefully I am doing something wrong?  Thank you!  

billsey

That uses a Mali-G72 MP3 GPU which should support FHD. The USB-C is as you say 3.1 gen 1, so limited to 5Gbps. Theoretically you should be able to run FHD at 72Hz, so 60Hz is pretty close to maxed out, but should be doable. I don't find any specs though that say what is supported...

Leostat

That sounds like the res of the internal screen, in the resoultion settings is it showindg one display or two? You could try checking and un checking the mirror the display box incase its not detecting it properly.

With the samsung, are you connecting it directly, or via the dock?

zman1

Thanks very much for the response.  I tried toggling mirror display but unfortunately it did not help.  The internal display resolution is 1366x768 and although looks nice I really hoped to use the portable external monitor at 1080p a lot of the time.  I also tried changing to the beta build channel which did not help.

Portable Monitor Setup:
USB-C High Speed Gen3.1 cable directly to portable monitor for Displayport and Power

Dock Setup:
USB-C dock with HDMI out to Portable 1080p 60HzMonitor
USB-C dock with HDMI out to Desktop 1080p 60Hz monitor

In all cases above the Galaxy sS8 cell phone can output 1080p @ 60Hz.  The Spin 311 is capped at 1440x900. 

I really like the spin311 but I think this could be a deal breaker.  

Thanks again!   

billsey

That uses a Mali-G72 MP3 GPU which should support FHD. The USB-C is as you say 3.1 gen 1, so limited to 5Gbps. Theoretically you should be able to run FHD at 72Hz, so 60Hz is pretty close to maxed out, but should be doable. I don't find any specs though that say what is supported...

zman1

I appreciate the input and fully agree with everything you say.  There is no piece of hardware that should limit the external display to below full HD.  Acer cannot provide the spec for this as well.  Unfortunately I think I will return this unit. Hopefully someone finds this thread before making the same mistake!