Any idea whats up with this Inspiron 7775 RX 580 Starcraft 2 glitch?

Bought a new, fully loaded Dell Inspiron 7775 27" AIO.
Overall it has been badass with no issues. But when playing Starcraft 2, after awhile it gets these pretty bad graphical glitches.

Any idea what is causing it?

Overheating or manufacturing defect is the most likely scenario.

If it takes a while before it does that, then something is failing or faulty when it gets warmed up.

AIO's are usually built with a lot of laptop components, and don't have very good heatsinks, fans, or airflow. They tend to suffer from overheating easily.

It appears my new computer is having some hardware problems.
Just ran Furmark and the issue appeared again. Looks like that on site service is going to come in handy.

try the newest drivers and if it still happens then I agree its a overheating or faulty gpu. if it under warranty, rma. if it out of warranty look for a way to mod it to cool better. clean it, widen slots, add an exhaust fan etc.

Last night, according to the Dell software (and their website) I had the latest AMD software and drivers.

I checked out the AMD website, and the Dell hosted version was outdated. I downloaded the AMD version of the RX580 drivers and installed them last night.
I played a quick round of SC2 and did not experience any visual glitches. I will try a longer run this evening or tomorrow and see what happens. Hopefully that is all it was.

As far as heat goes, I ran both a CPU and GPU 100% load stress test and no component went over 76 C during the 30 min test. So the system seems adequately cooled under load.