There's another power button push some newer folk don't know. IT MATTERS HERE!
Hold the power button for 4 to 15 seconds to force power off. If that fails it's the PSU or motherboard.
Bob
Yesterday my PC restarted itself without warning. After logging back on, I had approximately five minutes before this repeated. The second time I logged back on, it didn't restart again but blackscreened. My immediate reaction was yo turn it off by the power button but I was unable to. Now whenever I turn on my PC, I'm unable to even boot but the power of all fans and hardware seem to be active.
Hardware:
M5A78L-M/USB3 (if I read that off the board correctly)
Cooler Master GX 750W Bronze PSU
AMD 8320 Black Edition CPU
EVGA GeForce 660ti FTW Signature 2 GPU
OCZ Vertex 4 as my main
WD Black as my secondary
Cooler Master Storm case, cant remember which model but nVidia edition.
Tried Methods:
CMOS reseat
Hardware clean
Reinstall RAM to diff slots
Different PSU cable
Output from both GPU and Motherboard built in graphics
All methods yield the same power on, unable to turn off unless switching off the PSU and no booting up. If anyone could help with ideas as I'm not even close to tech savvy, I'd appreciate it. Thank you.

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