Screen flicker when change resolution on external monitor using mini displayport Fedora 34

hello everyone, I try to connect external monitor using miniDP (mini displayport) and success and stable, the external monitor got image, but when I try to change resolution, the external monitor become not stable, the external monitor become connect and disconnect everytime and cause my main screen flicker…

this problem appear when I try to change external monitor resolution to FullHD (1920 x 1080), but when I change to another resolution, no problem…
and this problem is also appear on miniDP… when I’m using HDMI and change resolution to FullHD, no problem…

I also try to reproduce this problem using Fedora 34 live USB (using Nouveau driver), and same, the problem is appear on miniDP and FullHD resolution…
I also reproduce this problem using Fedora 33 live USB (using Nouveau driver), but there is no problem, I can using miniDP and change external monitor resolution to FullHD…
I also remember, before I reinstall my laptop with Fedora 34, I’m using Fedora 33 with NVIDIA proprietary driver, there is no problem, I can using miniDP and change external monitor resolution to FullHD…

this is my system :
Thinkpad P52, this laptop route HDMI, miniDP directly to NVIDIA card…
i7 8850H
NVIDIA P1000 (yes, I already install NVIDIA proprieaty driver, but no luck, the problem is appear)
kernel : 5.12.6-300.fc34.x86_64 (I also choose 5.11 kernel when booting, but the problem still appear)
NVIDIA VBIOS : 86.07.63.00.76
graphic platform : X11

this is video when my main laptop screen flicker because the external monitor tried to connect and reconnect…
https://www2.zippyshare.com/v/ZBNOrtuq/file.html

is this kind a bug or can fix with additional config?? how can I solve this problem??
if you guys need log, tell me what to do, I will provide it…

It is really anoying this popups … do you really want help or do you just want promote zipshare?

oh, I’m sorry, thats the place I know to upload file… because I don’t see any form to upload video file in this forum and I can’t find any rules according to upload video files, if you have that rules, can you pointing me out so I can update my post… thank you…