How to fix terrible jitter on screen when using a 16.0" 120Hz display?

We're trying to use an UP Xtreme (the Celeron version) to run the Microsoft HLK test on a 16.0" 120Hz display.
For some reason there is terrible jitter on the screen. See the video in the linked zip file to see what I mean.
The jitter happens in the BIOS screen, as well, so I don't think it is a driver problem.
This exact screen works without jitter when connected to a Dell PC with a 7th gen Intel processor. (The integrated graphics controllers in 7th gen and 8th gen Intel processors are almost identical.)
The display also worked without jitter when I connected it to a Lenovo laptop with 11th gen Intel processor and integrated graphics.

A version of this display that runs at 60Hz worked fine on the UP Xtreme. But at 120Hz refresh rate it jitters.

I reset the BIOS settings to default, but that did not fix the jitter. Like I said, the display jitter is visible in the BIOS screens, so I don't think this is a driver problem.

How do we fix the jitter on the display?

Please help! We need to run the HLK tests as soon as we can, but the jitter is making it impossible.

The linked zip file has reports from CPU-Z and Intel System Support Utility for both the UP Xtreme and the 7th Gen Intel PC.

https://drive.google.com/file/d/1ReEgkAnZASW6WoWGTyqTjl_1Dr5xVHvT

Answers

  • Wilbert
    Wilbert New Member Posts: 55 ✭✭

    Hi Sir,

    Which display interface is it? We have three interfaces on the board.
    HDMI? DP? eDP?

    Best Regards,
    Wilbert Lee

  • razor1000
    razor1000 New Member Posts: 22

    @Wilbert said:
    Hi Sir,

    Which display interface is it? We have three interfaces on the board.
    HDMI? DP? eDP?

    Best Regards,
    Wilbert Lee

    It is the external DisplayPort connection.

  • Wilbert
    Wilbert New Member Posts: 55 ✭✭

    Hi Sir,

    Can you describe the overall system? Or a block diagram to make me understand the whole would be better.
    I have taken two UP Xtreme (Celeron) in my hand, tested the DP interface, and tested three screens of different brands and models, but did not see this problem.
    According to the pictures and videos, we suspect that it may be caused by unstable power supply of the screen/DP, but all this is just inference.
    If it is possible, can you help me confirm the DP signal to the screen, how many volts is the voltage?(3.3V?)

    (Remarks: Our DP interface is only used for screen signals, please do not use it as a power supply for other circuits)

    Best Regards,
    Wilbert Lee