Please make sure your PSU is properly connected, also make sure the wires of the PSU are properly connected.
I suggest to test your PSU to find out if it is dead.
PSU - Test DC Output Voltage -...

Does the system try to start a few times when you press the power button?

I guess you also don't have another cable to try?

Do you have something else to connect the monitor on? To find out if the monitor connection is faulty.

Please add in your system specs your hard drive(s), cooling system and PSU.

I can think of a few things that could cause a system to restart.
Please make sure your PSU is properly connected and...

I choose the second option ;)

Test your system and try to produce a crash, if a bluescreen occurs run the dm log collector again and give some description of what you were doing and of what...

Please uninstall everything of Nvidia using Display Driver Uninstaller and install new drivers from Nvidia. Be sure the clean install box is checked and only install the Graphics driver and the...