|Power supplies are not all created equal and 300 Watts on one does not mean the same as 300 Watts does on another. List the Brand name, The Model number, and the DETAILED specs (most important would be the Amperage on the 12 Volt Rail(s)) for us to really help you. I suspect an inexpensive 300Watt power supply which has inflated numbers, but not the right numbers. Inexpensive power supply makers often inflate the 5Volt and 3.3Volt rails which is easier to do but which will not really be of any use. inexpensive power supplies are lower on their % efficiency so that you get less out of them compared to more efficient models.|
You have to be a little bit crazy to keep you from going insane.