I can't tell what triggers it, and I don't see anything glaring in Task Manager or Event Viewer, though I don't pretend to be expert enough to spot the problem. Drivers are up to date, NVIDIA GeForce GTX 1050 Ti.
@James_H
Sounds like a broken notification. Can you get rid of it or do you need to restart your PC? If you're having to restart, instead do Control + Shift + Windows + B. That'll reset the GPU driver, see if it's just something that's getting stuck in the frame buffer.
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