[STRML]

If you have two monitors, this doesn't make much difference. I'm at 19W with HiDPI off and 20.2W with it on, with 2x 2560x1440 Dell U2515HXs.

[seam_carver]

That's unfortunate, but does 1 monitor/lid closing make a difference?

[STRML]

It does seem to, yes.