The thread linked above has a fix in the latter problem that actually seems to point to the power supply, and that is likely why this seems to be hit or miss: "Because your system still freezes, it could be due to cross loading problems which can result in the power supply turning off when a load changes or result in voltages becoming out of specification causing system crashes and hangs. entire CCX or Core complex is taken down."

Setting "typical current idle" in "Power Supply Idle Control" in the BIOS seems to solve the problem here. Comments in the kernel bug report regarding this also show that this apparently solves the problem.

https://bugzilla.kernel.org/show_bug.cgi?id=196683