I have the cooler master extreme power plus 500w, but idk if that will work and it is pretty loud! If my cooler master psu will work fine I will probably keep it even though it is a terrible psu. Is it normal for the fan to be pretty loud? It doesn't buzz or sound like it's rubbing it is just a loud fan noise even when I'm just browsing the internet. I will buy a better power supply and return that one if the fan being loud isn't normal and if it won't work for the 7850. I believe it is rated at around 430 watts and I'm running an A-6 3650 apu so my system doesn't need much power, but I'm still not sure if it will work alright.