Note: First and foremost it will not power up because the power-on pin (#14, most often green cable) is not connected to ground (any black cable). https://www.

Note: First and foremost it will not power up because the power-on pin (#14, most often green cable) is not connected to ground (any black cable). https://www.google.de/search?q=atx+power+supply+pinout&client=chrome-mobile&tbm=isch&tbo=u&source=univ&sa=X&ei=yFqBUYe4M8ml4ASog4DwDw&ved=0CDQQsAQ&biw=320&bih=460#i=6 https://www.google.de/search?q=atx+power+supply+pinout&c... The most likely outcome though is that the supply will just power on and idle without any load. Rapid transients on the rails (say from 100W to ~0W) might cause the over voltage crowbar to trip, though.