Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Unit was DOA

I was very impressed with the build quality of this PSU. Unfortunately, the one I received did not work. I was building a new system and originally thought the new motherboard was DOA. After confirming it was indeed the Thermaltake 430W PSU that was non-functioning, I returned it. I give Amazon.com an A+ for their return policy. In the end, I decided to buy another brand at a local BestBuy store.