Not trying to necro this old thread but I had a similar situation on my maximus vii hero where the power light started flashing like it had a short in it as the light strength seemed to be lower than normal. A flashing power light usually serves as a reminder indicating that the system is in sleep mode but this was not the case as with the OP's system.
I checked around to the front panel connectors on my easy connector and the power leads had come lose backing off their connectors just a bit so I seated them all fully and the issue has not recurred.
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