Hi,
Well, I don't think this is a software issue because I have the G16 (2026 model) and am experiencing the same problem. I tested it with Windows 10, and it doesn't happen as frequently. However, I noticed it occurs more often when the display is running on the Intel iGPU; if I switch to Nvidia, it happens less, though the color and brightness still adjust gradually.
I know it's related to the Armoury Crate software: the problem didn't occur when I hadn't installed it, but the issue returned after I installed it following a Windows reinstallation.
As I said, I don't think it's Windows; rather, it seems to be a hardware fault with the screen itself, as the behavior varies. I've already contacted support regarding the warranty and am waiting for a response.
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Thanks.