Are all the bios settings on their default value?
Can be caused by an unstable overclocking or a faulty hardware.
I think, like with the CH6, there's a chip either getting too hot, or receiving too many bad commands, that's resulting in this nonsense. I say this, as my CH6 Wifi will run for days without issue, then suddenly die; machine needs to be fully switched off, and then switched on before it will work again, and this is with top of the line components. Perhaps it's the VRM? But I want a program or logger or something to find out the problem definitely before randomly swapping even more components at this point...Event Viewer shows nothing worthwhile.
Elmor confirmed that Corsairlink software will also cause random shutdowns: if you have it installed.