But the package HAS changed. The ram is more energy efficient, but it is now clocked higher and there is more of it, so that negates the energy savings.
Same with the screen, it may take less power to light up each pixel, but there are now more pixels to light which will again negate the energy savings.
Also, you can't just stack the energy savings, it doesn't work that way.
Now if they kept everything the same then you would see those energy savings.
Acording to display mate the note 4 screen got brighter and got 14% better power draw vs the older 1080p note 3 screen.Samsung is going to use this same tech from the note 4 to the gs5.
ddr4 ram as a standard will consume less power then ddr3 and clock faster.the ram is also being made on a smaller node from the same ram used on the gs5.
Samsung is also using a class 10 let modem that will consume less power then the old gs5.
Here is a clip from display mate about the note 4s power efficiency