I've just unboxed my brand new (Nov 20 Build) G9. Plugged it into my PC and the whole screen was flickering. Updated the firmware to 1008.1 (nothing to say about that, its already been done..) and no change.
I had ignored one step in the instructions, I had left the existing Ultra High Speed Display Port Cable that I had bought for my previous monitor.
Tried the cable that was shipped, and no Flicker.
Just posted this incase someone else makes the same mistake.
I am now happy!