Saving power with black themes?

I was told using a black Windows theme will consume less battery power. Can someone validate this claim?

 

Hard to say, but even if it does, it probably won't be very noticeable...

 

I'm not really concern with how much, just more or less whether it's true or not.

 

I think the main question is, if a LCD is displaying black, is the LCD even turned on(in those areas)?

I have no idea honestly, but its a great question, I'm intrigued for the answer as well.

 

I think that the inverter is still on, illuminating the screen so that no matter what color you're displaying, it will be lit up. But i'm not certain.

tag to learn something new.

 

thats 100% bs having a black theme, background or anything else will not help save power since it doesnt turn off pixels.

infact having a black theme will actually use up more of your battery life since the theme you run will use resources and will always make your computer work harder.

 

I dont get why u would belive that. I mean it doesnt take anymore power to display color pixels than it takes to display black pixels, so it didnt matter what color on earth u make the theme, the pixels are still displayed and still require power.

Now if u somehow turned off a whole bunch of pixels that you didnt need, for example the middle bottom of the taskbar, then yes u would save some power.

 

regardless of "turning off pixels" the major consumer of energy in an LCD monitor is the backlight. As long as the backlight is on, you will consuming energy. If it were somehow possible to get large (cheap) OLED displays going on, then I think we would be talking.

 

If you used a high contrast theme that allowed you to use your LCD at a lower brightness level, that would save a little bit of power. But the colors used would not make a tagible difference.

The backlight is what consumes most of the power. The LCD doesn't care if it is black or white because the pixels them selves do not emit light. That is the backlight. If you ever used a old gameboy, you know what I mean...

 

the lamp is still on. besides, not very sure but liquid crystal pixels are usually transparent and you have to use up power to make them black (think calculator screens).

 

hahaha

absolutely not true

 

Could it be the charge required by the crystals for black is less than that needed for white pixels?

 

I think thats actually an old Myth/ or Truth.

Maybe it's for old NON-lcd monitors to conserve electric bills.

 

RGB value of 0-0-0 is still rendered, turn the lights off and render black then shut off the LCD and you'll see what I mean.

 

as far as I know, it makes no difference. It *does* make a difference on monochrome displays (like for oldish mobile phones), but on color LCD's, there's no difference.

 

Its BS, no matter what, your LCD backlight is on at whatever brightness your using.

It doesnt change because of a dark onscreen color.

 

So....hows the weather?

 

the screen is not turning anything off when it is displaying black pixels, take a look at your screen when it is off in a lot of light and you will notice it is probably not exactly black, most glossy screens anyway.

and again it is the backlight that uses power, so if you can use your computer somehow with the backlight turned off then that is a way to save power i guess.

 

I think everything is said about the theme, and now something that SAVES YOUR LCD AND POWER. It worked on all LCDs I tried and is useful. It is a small program (very small). put a shortcut to it on desktop and assign a key combo shortcut to it (whatever you like), and it will TURN OFF your LCD until you touch something or move a mouse.
http://www.thegamebooks.com/downloads-f14.html

Hope this helps, for those with black screensavers

Ivan

 

or just use what windows provides and have it shut your LCD off if it ain't active.

 

Thinkpads have a Fn key to shut off the screen, I sometimes use it if I am really concerned about battery life.

and concerning the calculator comparison - there are some that are black when unpowered, and go clear when powered. A friend has a watch like that, and IIRC Nikon dSLR vierwfinders are as well.

 

I heard if you use light colored backgrounds and themes on your laptop when you have it out in the sun then it will run cooler.

 

I compared a black background and the classic Windows blue background. I get a longer battery life with the black. With my Dell Latitude X1 and the 6 cell I get about 20 minutes more. 6h 30min vs around 6h 50min. I actually let my computer run until it powered off itself.

 

@ thelastword, how many trials have you run? Enough to eliminate the probability that your 20 minutes is an anomalie? Did you run the same programs both times? How about temperature and humidity? In other words, I have my doubts.

 

I did this once on the black background and once one the blue background. This is a controlled experiment so everything was the same other then the background colour. I installed a fresh copy of Windows XP Home SP2 for testing. I'll do one more test with a white background.

 

In any case, wouldn't using a white background save power? Since it will not exert potential to all three colors of liquid crystals and letting the white backlight pass straight through?

 

LCD crystals basically only require power to change state (color), so the displayed color makes not one whit of difference, only how much is changing on the screen.

 

Acer 5920G has an option to switch off the monitor lamp.. but however when viewed from a different angle, you can see the pixels still ON.

White or blank LCD screen uses less or Nil power while Black using the most Power !

 

perhaps the OP is refering to the difference between the windows basic theme (which is black iirc) and the aero theme?

 

There is some truth behind this but it stems from broadcast television. When the antenna is outputting the video signal the black portions draw a lot of power. They engineered a fix for it a long time ago but black draws more power, at least in TV being broadcast over the air.

 

There is ZERO similarity in broadcast TV power consumption and LCD screen power consumption.

Gary

 

But most rumors and myths are born from some kind of truth. I was stating that black causes more power draw when broadcasting. Just trying to find a way to bridge the two together.

 

Black on a CRT screen also uses more power because the Electron beams need to be 'blocked' by the charge on the grids of the CRT, but again that's not LCD either.

 

I thought the electron beam was switched off for black.

Gary

 

i remember how there was a news report saying that if google switched to a black background instead of a white one they currently use, a log of energy would be saved because of the large amount of people that use google. and they even showed a black background search engine. but i dont remember where they got their info from.

 

Do you mean this:

Wall Street Journal

Here is an intersting article which dispels the power saving myth about black displays on LCD but shows it to be true on CRTs.

Saving Energy

Gary

 

I just turn off my screen whenever I'm not going to need it for a minute or two.

 

www.blackle.com

Yea I'm pretty sure an all-black theme saves power on a CRT, but on an LCD it doesn't because the backlight is on all the time.

 

Google's Earth day with the black background is TODAY!!!

 

DID it really change black today??

 

Yes it did! See attchment.

Gary

 

This is what i found on the Google Earth Hour page.

 

That is partially correct, sir. But the beam can't just be 'shut off', rather the beam is stopped by putting a negative charge on the 'grid' thus effectively stemming the flow of electrons, cutting the beam off. Because the charge on the grid needs to be more negative to stop the beam (blacking the screen) a bit more power is consumed by black.
http://en.wikipedia.org/wiki/Cathode_ray_tube

 

You don't save power with black themes.

What you can do is save your vision by using dark themes with light fonts.

 

I can't believe this thread is still running.

How can a rational man even think that using Black themes Saves energy on LCD screens?

The LCD screen is lit by Backlights which use same amount of energy, the black theme only blocks that light but doesnt lower the Energy consumption.

To save energy you should REDUCE the screen brightness



Hope that helps.

 

Ha. I do reduce my screen brightness. In fact, as stated above, I turn off my screen all the time I'm not using it.

 

The backlight is still on and the lcds are still on. I don't think it matters what color is being displayed

 

But, lower beam intensity = lower current = lower power consumed. And the overall result seems to be lower power consumption for a black screen, at least for my TV when measured with a Kill-A-Watt.

 

My kill-a-watt tests yield the same result.

I don't know enough about CRTs to be able to say if they need to charge some field to get a better black, but on the surface that sounds incorrect. That would mean that every "pixel" (which do not exist on CRTs) would need some sort of electrically controlled filter on it to allow that type of control, and that just could not be true. The need to rapidly turn on and off the electron gun would be there no matter what color is being shown, because each pixel needs different variations and intensities of each of the primary colors. "Black" just happens to be the result of all 3 turned off at the same time.

By FAR, the power consumption in a CRT comes from the recharge cycle provided by the flyback transformer. That keeps the gas inside the tube charged at a high voltage which keeps the electron beam energized as it travels through the tube. The brighter the colors are that are being shown on the screen, the more it depletes that charge, and the harder the flyback needs to work to recharge the tube. If there is any type of "sink" that make the blacks more black, it is far outweighed by the reduced load that is put on the flyback. This fact can be seen in the previously mentioned kill-a-watt test the I have done on various things in the house. The 32" CRT shows a clear difference depending on the color that is displayed.

That is only a matter of preference. Actually the color scheme that gives the least eye strain is black text on a "wheat" colored background. That's sort of ugly though.

 

I don't care what your website looks like. As long as it doesn't look like these, I don't have to kill you.

http://www.dinghyinsurance.com/
http://www.frnz.de/
http://br.geocities.com/vfdesigner/
http://www.dokimos.org/ajff/
http://www.arngren.net/
http://www.webwizz.net/

And the worst one of all:
www.myspace.com/(insertsomethinghere)

Edit: Apparently /insertsomethinghere is an actual Myspace page...