Are you using intense live traffic (either Asobo’s or VATSIM or FSLTL)?
You may also test your RAM, but if this happens only in VR the reason is probably somewhere if you setup, but I never experienced anything like this (Reverb G2, Pimax Crystal).
Do you have resolution override in OpenXR Toolkit? What is your resolution?
Consider troubleshooting:
- switch from PimaxXR to SteamVR OpenXR runtime,
- disable OpenXR toolkit.