lol 1100w i do believe is ridiculous, and I have seen alot of machines with psu that is over 500w, my computer was 2.5ghz dual core, 3gb ram, 256mb graphics (so the card wasn't even that much) 1 80gb sata II Hdd, 1 dvd rom, 2 case fans and a 500w PSU. I decided to buy a second HHD 500gb Sata II, plugged it in made sure it was connected properly before turning on. Turn the computer on I had to press the button 5 times to finally get to power up. I upgraded t a 750w, No drama it now works. (you are probably thinking faulty PSU) Wrong! I plugged the 500w in my older machine that is only a single core 2.8ghz, 512 mb ram, 64 mb graphics, 2 IDE HDD's and 2 case fans and it is working fine.
So from my experience you got to understand why I think 300W is not the go with modern technology.