If you look right above the final box on the bottom "650w" you will notice there are several accumulative boxes above that containing 100w, 3.5w, 0.5w 15.6w, 650w, etc. That doesnt add up to 650, that adds up to like 770w. Thats not the output, thats the theoretical output pre efficiency. The box underneath that is the post wattage calculated for efficiency