Any affordable quiet 400w ATX power supplies?

[Derek Semeraro]

Fanless power supplies are an option, but in mid-range builds, a fanless PSU is money that could be spent toward the processor or RAM.

Is there a power supply that is ATX-sized, ~$50 (or less), has at least 400 watts of capacity, while also being quiet (<25-30 db)

[lodestar]

If you were willing to stretch the budget to $80 then for this money the obvious choice would be the Seasonic 550w Focus Plus Gold which is available from sources such as Amazon. As you can see with Amazon there is an additional price reduction through rebate that brings the price down to $69.90 with free shipping so it would in practice only mean spending another $20.