Sorry it took so long to post an update, I had surgery; my pectoral muscles were dissected and two large foreign objects implanted under them, and if I had done anything crazy like trying to lift a giant Cooler Master HAF 932 case with dissected pectoral muscles, I would have caused internal bleeding, but yesterday my nurse gave me the all clear to resume normal strenuous activities, so I think I'll be good to go with lifting my PC again.
So I called Asus support up again, and they said that they're sorry, Advanced RMA is not even an option for this motherboard at all, it's not an issue of them being low on stock for Advanced RMA. It will have to be a regular RMA. Which sucks, because that means instead of simply uninstalling the new motherboard and installing its replacement, I'll be uninstalling the new motherboard, reinstalling the old motherboard, then uninstalling the old motherboard and installing the replacement new motherboard. Ah well.
For future reference, which motherboard manufacturers still allow for Advanced RMAs, so that I don't have to go through this again?
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dorkenstein3
It's not Hybrid Sleep, that was the first thing I tried. It's not even just Sleep. It's Sleep, Hibernate, and Shut Down, in Windows 10, Linux, and the BIOS. The PC refuses to turn off unless I switch off the power to the power supply, regardless of what OS it's running and what settings.