Pebls2 :
Try to run whocrashed anyway.
Usually the power supply is the culprit in issues like this (if it's not cause by drivers/software anyway) but since you have a new one that is from a reputable brand with more than enough wattage i don't see how that could be the case unless you got unlucky and got a broken one..
You can also try re-seating some of the components (though don't do it with the CPU if you don't have any thermal paste lying around) and checking if everything is plugged in properly..
the whocrashed thing
Crash Dump Analysis
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Crash dump directory: C:\Windows\Minidump
Crash dumps are enabled on your computer.
No valid crash dumps have been found on your computer
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Conclusion
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Crash dumps are enabled but no valid crash dumps have been found. In case you are experiencing system crashes, it may be that crash dumps are prevented from being written out. Check out the following article for possible causes: If crash dumps are not written out.