32 Z77 motherboards compared @ Hardware.info

The idle power consumption ranged from 24W (Gigabyte GA-Z77MX-D3H MicroATX) to 54W (Asus P8Z77-V Premium ATX). Load power when running 3DMarkVantage varied by 30W and when running Cinebench by 25W.

In general, more features = more power. I haven't had a chance to look in detail, but Asus seems to be a bit more power-hungry than it's peers for a given feature set. Bummer.

Lovely article. Kudos to them. Ideally I would have liked to see what voltage the boards gave the cores during load, as there might be some variation there I suspect.
MSI Z77A-GD65/GD80 looks like a good bet if you want an ATX board with plenty of features and still good idle power consumption.

True - but, at idle there's a 30W variance from best to worst and at load it's still 25-30W sorta implies it may be more the VRM configuration/efficiency and the various features added on (extra LAN, Thunderbolt, etc) that affect it more. I haven't had the opportunity to delve deeper, yet.

I'd love to see a roundup of H77 motherboards.