PC turns on, but no display

In December I bought a gaming PC. It turned out to have a defective GPU, so I exchanged it for the same model at the store. That model seemed to be in working order until yesterday when I got a temperature warning of 77C at light load and repeated voltage warnings from Aegis III, ASUS' monitoring software. It would say "9.600 v!" Then tonight, when I turned the PC on, there was no display. I checked the power cord, plugged the (brand new) HDMI cable in and out of the monitor and even tried a different monitor to make sure that wasn't the culprit. No luck!

Is 9.600 v too low or too high? Is it possible that it's a defective power supply?

UPDATE: I tried unplugging the power cord and holding the power button for 60 seconds. That worked and I'm using the PC right now. But I'm still wondering what the source of the issue is.

CountMike said:

9.600 v, as in Volts ? Where ? If on graphic card and it's GPU that would instantly blow it up, typical voltages are ~1v. That reading should have been 0.960v.

I don't know. I screen capped the alert yesterday.

CountMike said:

Oh, that's for 12v branch from PSU and or VRM (Voltage Regulator Module) on the MB. Your PSU may be bad.

If so, is this a danger to other components in the PC? I assume I should discontinue use until I get the PSU replaced.

CountMike said:

It might make problems but should not burn anything. PSU can be checked for voltages and operation with right equipment but to some degree with ordinary voltmeter. Any Yellow and Black wire on main, 24pin connector, should read 12v +/- 5%.

Unfortunately, any poking around will void ASUS's warranty. Then again, the amount of trouble (and I believe some cost) of sending it to them for repair may not be worth it if it's near certain to be the PSU that is the problem. I could get a voltmeter and test it, or easily swap out the PSU myself.

I very much appreciate your help, CountMike. I'm not sure this one is solved yet but I will surely update this thread ASAP.

Update: No confirmed diagnosis but the PC is being shipped out for repair and will return within a couple of weeks. If I open it up, my warranty with ASUS will be voided. Bummer.