No, my bug did not seem to be that problem. It would not freeze but just reboot. Oddly it got worst as time when on. Initial I could boot into Ubuntu, then only to grub, then eventually it would reboot as grub was loading.
When the CPU was replaced with another Ryzen CPU everything worked fine. I have not had a reboot or freeze since then.
By the way I was stymied trying to diagnose the problem so I took it to Memory Express where I bought the parts. They charge $50 for the first hour and did figure out that it was the CPU. I was pleased with their work. Never charged more than that first hour.
On 2019-01-22 1:22 a.m., Trevor Cordes wrote:
We had it freeze within 5 hours of first booting. Apparently there's a nasty chip "bug". If your reboots were more like freezes (or even if not), you might have just been hitting this bug.