What Power Supply Unit (PSU) does an AvalonMiner 741 require?

You need to buy a power supply (at least 1300 watt) like this one:

PSU Recommendation on Amazon

Or, you can do like 2 x 650 where one is for left side and one is for right side.

Canaan does not currently supply PSU because often it is easier to source in your home country and many miners already have PSU available. For orders over 50 units, Canaan may provide a PSU on demand.