[Help] Higher than expected refresh rate on Odyssey CRG9

[dsf190]

My dad recently purchased a Samsung Odyssey CRG9. He tried connecting it to his Surface Book 2 for testing via the USB-C port on the right side and we noticed that the refresh rate was locked to 59.917hz at the native resolution of the monitor, 5120x1440.

 

The problem I have with this is, according to Microsoft, the USB-C port is USB-C version 3.1 Gen 1 with USB Power Delivery revision 3.0. From what I can find, this has a maximum data transfer rate of 5Gbit/s; however, according to the calculator on this site, the resolution and refresh rate combo it's currently running at should require 11.07Gbit/s.

 

What am I missing?

[Levent]

I am not entirely sure as most USB3 protocols are still a mystery to be but, maybe it’s running on usb DP alternate mode?

[GuiltySpark_]

@Leventis correct, while MS doesn’t seem to specify it, most laptops these days support DisplayPort Alt Mode over type C natively. 

[SquintyG33Rs]

it's DP alternate mode. it doesn't use USB data transfer spec. it's probably DP 1.4 if you wanted to check what kind of speed it can do.

 

it doesn't need to support the thunderbolt extra stuff to be able to switch into DP mode.

[Glenwing]

https://linustechtips.com/topic/729232-guide-to-display-cables-adapters-v2/?output=USBC

Quote

The DisplayPort signal sent over a USB Type-C port is exactly the same as the one sent over a normal DisplayPort connection. There is no compromise in image quality, features, or bandwidth when using USB-C. The video signal is not limited by the 5 Gbit/s or 10 Gbit/s bandwidth of the USB transport protocol, because the video is not sent using USB. The port simply acts as a passthrough for a native DisplayPort connection from the GPU, and the full DisplayPort data rate is available through the USB-C port (17.28 Gbit/s for HBR2 or 25.92 Gbit/s for HBR3, depending on what the graphics card supports).

 

[dsf190]

Dang, I was on the right page and scrolled right past the answer  thanks everyone!