Did GPU upgrade: GTX 1070 ==> RTX 3080 // horrible screen flickering and laggy

[jsdrifts]

as title describes, Did GPU upgrade: GTX 1070 ==> RTX 3080

in fact I upgraded the entire PC, switched from small form MSI Trident arctic 3 to a HP Omen 30L. the pre build just was a lot cheaper compared to self build.

Everything runs great, except iRacing, and let that be my preferred sim...
I can get lots of FPS, but the screen flickers, sometimes its way too dark, than flickers back to normal. Skies (are on low) sometimes load a second later. Although FPS are high, it seems laggy in a way, like it skips some frames.

My previous PC ran I racing at 90 fps and was really smooth. Now I run at 120-240 FPS and it isnt smooth. I really have no idea what I can do.

updated drivers, did clean install,... MAybe a setting?

My screen is a samsung 49 ultrawide. 5120x1400 on 240hz.
previous PC was same screen, but on 120hz

 

[Kurupt CDN]

Have you rerun the graphics config in settings?

also, in-game have you redone your monitor settings in the graphics settings top right? ex. width, monitor curvature and correct resolution