Q: My computer, an HP m8200n Media Center PC, has a 300 Watt Power Supply, but I am buying a 9600 GSO which requires at least a 400 Watt Power Supply. According to this guide: http://tech.yahoo.com/gd/improve-pc-performance-replace-your-power-supply/166304 It says the wattage of my new power supply must match the wattage of my old one. Does that mean I can't upgrade my computer's power supply to a higher wattage? This is the power supply I plan to buy: http://www.circuitcity.com/ccd/productDetail.do?oid=215806&cm_ven=COMPARISON%20SHOPPING&cm_cat=PRONTO&cm_pla=DATAFEED-%3EPRODUCTS&cm_ite=1%20PRODUCT&cm_keycode=635869&om_keycode=635869
A: If you really wants to but something rated close to 400W, you should get some good brands, that is True Power rating. 450 is not the real wattage. nothing can be 100% efficiency, but good power supply can come close to 85% efficiency or even more cheaper ones could be 50% efficiency or lower, so be careful there