These days its not out of the realm of possibility to find a reasonably price power supply that has a decent amount of wattage and power efficient. The Corsair CX Series CX750M 750 Watt ATX Modular power supply is no exception. For a mere price of $89.99 this power supply which I found on Micro Center is a excellent choice for PC builds and upgrades. In fact believe it or not,I have the very same power supply unit in one of my computers so I can most certainly attest to its high quality.
The Corsair CX750M power supply has very low noise meaning it runs extremely silent, there is little to no detectable fan noise,it's very flexible with modular cabling, you only need to use extra cables if needed. It has a 80 Plus certified efficiency rating,so there's no impact on your electric bill.
If you're looking to not spend a mass amount of money on a quality power supply,the Corsair CX750 would be your best choice.