11-08-2017 01:42 PM
I am using a usb-c to hdmi adapter to output to a TV but the black levels look washed out. I had no issues with the same TV and a previous laptop that had a dedicated hdmi port. In the intel graphics settings usually there is a "quantization range" setting to change color space between RGB Limited and RGB Full if the intel graphics is driving the hdmi port. However, in this case, there is no hdmi port but instead a usb-c to hdmi adapter, thus the quantization range setting is missing. I've had the same issue before on a previous laptop with usb-c. I've tried installing thel atest drivers, including the non-validated ones from the intel website, but none give me the quantization range setting.
11-03-2018 10:48 AM
Same here. Been having this problem for months since I purchased. but I havent been able to find a solution.
Black levels are really bad when I connect a second monitor using any USB-c hub. Blacks are greys on the external monitor. Seems like the full vs limited range toggle switch but as you noticed the option is not available in the driver panel.
I am assuming its an intel graphics driver problem but good luck getting an update these days to the current versions of intel drivers.
11-03-2018 07:40 PM
Welcome to the Community,
There is an existing thread that is similar to USB-C to HDMI issue on Yoga 920,
You may try the suggestion solution and see how it works. Some users also has a suggestion from the thread that you can check.
12-29-2018 02:32 PM
Has anyone found a solution to this specific problem? The thread linked above is "similar" but not the same problem.
The root of the issue is the RGB limited range on the updated Intel drivers when connecting with a non-native HDMI, i.e. a USB-C dongle or hub, as discussed in this thread and many others:
Manually downgrading to the 15.45 version of the Intel driver *does* fix the color issue, so we know that the UHD 620 can in fact display colors properly. However, I also found that this older driver version (direct from Intel, not Lenovo) will crash any time you try to play or even preview a video file, so not a workable solution. Also, using the newest driver, the registry entry suggested by one of the users on the Intel forums seems to have no effect on the Yoga 920.
The behavior is exactly the same whether I'm using a directly connected OEM HDMI dongle from Lenovo or a USB-C hub with HDMI.
For me, the color was fine when using a DisplayLink-based USB hub, but I wanted to get away from DL because the same thing that makes the color work (proprietary display driver) is also what makes it a glitchy resource hog.
Side note: my monitor has DVI in, and I am using an HDMI-DVI cable. However, as noted, this should make no difference, as I've seen full RGB range pushed through this same setup with the older driver.
Considering Lenovo chose the UHD 620 for the Yoga 920 while not including any kind of display port other than USB-C, and Intel cIaims that USB HDMI connections are not fully supported, I should hope that Lenovo would work with Intel to provide a driver that delivers full resolution and color depth. Please deliver this, or some other workaround!
01-06-2019 02:50 PM
Have you tried the new display drivers from Intel ? they recently started releasing Windows DCH Drivers making installation possible on many laptops. Before I was not able to install intel drivers (using exe installer) other than the ones lenovo supplies which are now super outdated and propably buggy. If not mistaken lenovo recently published 188.8.131.5273 while intel is at 184.108.40.20671.