I've got a two-GPU computer. If I'm using GPU preview mode, after working for a while (around 20-30 mins or more), the entire Illustrator UI will glitch out and become very artifact-y and unresponsive, and I can no longer work on the files I've got open, necessitating a restart of the app.

This started happening right after I upgraded from one GPU to two, about a year ago. It happens only in GPU preview mode, not CPU. I've tried updating GPU drivers, updating Illustrator itself--nothing fixes the problem. I've seen other people online with multi-GPU setups say the same thing happens to them, so I'm not alone.