Power consumption of a pixel determined by its size?

[Rojlani]

Hi,

is the power consumption of one pixel determined by its size or not? (say if lcd and if amoled)

thanks

 

[Crashmaster]

your question is not really clear.
A pixel is the smallest addressable graphical unit and it's usually 32 bit for a PC/laptop
The electrical power consumption is device specific. So an LCD and a LED screen will consume power according to how they were built in terms of technology and efficiency.

 

[MarkW]

I want to see you get out a voltmeter, and measure the power draw of a single pixel and ONLY a single pixel.... :lol:

Actually, I think the backlighting is the big power draw in most monitors. AMOLED does provide its own light, and the new Quantum Dot monitors will as well. So those probably will pull less power than backlighting, since its all integrated into one layer of technology.

I am sure that each pixel does have a factor on the overall power draw, but considering that a 1080p monitor has over 2 million pixels, the power draw is a very tiny little number per pixel. I'm coming up with .0000217013888 watts per pixel for a monitor that draws 45 watts.

 

[Rojlani]

ok - thanks for the info,

i am interested in mobile devices particularly - say Phone 1 has a display 6" 1080p - Phone 2 is 6" 720p - both lcd. Will the display of P1 need more power? And If they were amoled?

And another case - P3 is 6" 720p - P4 has 4" 1080p.

Same as if the case was with laptops (with other sizes).

hope this time it is clear

 

[MarkW]

The power draw on those is much more influenced by the back lighting than the resolution. The GPU works harder too, but even that is a pretty minor increase, unless you are gaming on a phone. Watching movies on your phone also uses up a fairly significant amount of power, especially if its a 1080p or 1440p movie.

 

[Rojlani]

You say by the back lighting - that is - the bigger the display, the more power consumed?

My experience is with a 2hour 720p movie - a 6" LCD phone (5W CPU) needs 16% - and a 13.5" LED tablet (15W CPU) takes 42% - both devices 1080p.

But i want to know in particular for Microsoft Office - there the CPU is almost fully resting but the screen is white. The power consumption on the phone is nearly the same as with the movie.

In this Office scenario - is it really only the size of the display regardless of the pixels?

 

[MarkW]

A white screen obviously is going to use more power than a black screen. It takes power to turn every pixel on. You save power if every pixel is off.