micro-ATX PSU and A4000D

[bigwall68]

I am sure this question has been asked a ton, so apologies up front.

Just got my hands on my dream amiga, a 4000(rev B), and looking to replace the original PSU.  

I see the adapter to purchase however what watts/volts/amps etc should i be looking for to replace it?

Thank you - Craig

[bigwall68]

Thank you.  What about output amps and volts?