AMOLED power consumption based on pixel color?

Working on a watch face for the EPIX 2 and was wondering if a white pixel would use more power than a green or red pixel.  If a white pixel requires turning on the R, G and B pixels, I would think that using one of the primary colors for the display in sleep would use less power than using a white pixel.

Does anyone have any data or thoughts?  Would using just red or green while in sleep mode be better than displaying in gray?

Thanks,

Paul