I yelled really loudly, then cursed a bit.
None of that seemed to help, so I headed here before sending it back for warranty repair.
Restarting it, clears it up, but as soon as the video rendering starts, the checkerboard is bound to return. Sometimes it does, sometimes it doesn't. Frustrating really, otherwise, I'd say it was a video driver Vs the software.
There have been various graphics glitches reported here, but mostly early before the latest OS. Unless you're running some unusual software that would impact this, it's likely hardware.