Question Screen blinking when at idle new gpu

[mkdgamer907]

Recently i bought a Sapphire RX 6600 gpu from my local computer store and when i started using it i noticed its not as smooth as my gtx 1650 in desktop and idles, Than I was watching something on my second monitor while using the first one to google something and it started like fickering but it wasnt the monitor 100%, I gave them the gpu back said its broken they tried to replicate the error but they couldnt, than they allowed me to get another gpu if i payed additionaly and i got an RX 6700 for like 80bucks more and the Sapphire RX 6700 is like only in europe or somehting so it isnt that popular, I thought that would solve my issue but it didnt its the same <Mod Edit> again, and its only in idle under load it doesnt have like alot of problems maybe on some games it would lag like a little bit but not too much or maybe its just streaming in the textures for example and then it would stop fps dropping but whenever its at 0 load or like low 20% load it does that <Mod Edit>, I tried a weaker gpu a RX 5500XT and there were no problems, I think that my PSU or my motherboard is the problem here are my full pc specs
CPU - Ryzen 5 3600 No overclocks
GPU - Sapphire RX 6700
PSU Sharkoon WPM 500W bronze
Motherboard - Msi B450 Pro M2
Ram 16gb hyperx something somethign but ram probablly isnt the problem

here is a video of the problem, I need to know if its the gpu or motherboard so i know what to replace my budget is limited

View: https://youtu.be/lOR7hldnPKA

When i have something like a video on fullscreen on my second monitor first monitor google and apps will flicker but if i dont do anything on my second monitor and work on my main most apps dont flicker except photoshop premiere and stuff like that idk why

 

[Lutfij]

PSU Sharkoon WPM 500W bronze
How old is the PSU in your build?

Whn you swapped out your GPU's did you use DDU prior to removing your initial GPU in the build and for everytime you swapped the GPU for something higher in tier?

 

[mkdgamer907]

PSU Sharkoon WPM 500W bronze
How old is the PSU in your build?

Whn you swapped out your GPU's did you use DDU prior to removing your initial GPU in the build and for everytime you swapped the GPU for something higher in tier?

I did use DDU and its so annoying i swapped the gpus like 10times and used it 10 times i cleared out everything i dont think the drivers are the problem tho
the psu is probablly like 4 years old maybe 3 not sure