This PSU offers quiet operation and performs fine. DWC gives it a Recommended Product award.
"In my first Sentey power supply review, I have the SDP650-SS 650W power supply here today. The SDP650-SS is an entry level 650W model. For around $80USD, the SDP650-SS gets you a non-modular, 80PLUS certified supply with a quiet 140mm fan and a 5 year warranty!"