I have two desktops, the one I'm working on is a Win 7 ASUS MB has the problem, the other was reported here.
All the checks in the first link above were done.
The first event log entry for the rogue power up was for the APC UPS: "PowerEvent handled successfully by the service." The security auditing for event 4672 is the same whether the rogue presses the button or I did.
However, the second system entry for the rogue power up is
TCP/IP NetBIOS Helper param2 stop param3 0x40030011 param4 Operating System: Network Connectivity (Planned) param5 None
For the human power up there's
param1 TCP/IP NetBIOS Helper param2 running
POWERCFG DEVICEDISABLEWAKE disables the device from waking the system from a sleep state, but what about from hibernation?
powercfg -lastwake provides no help.