How much battery life is used by monitor?

[dimon]

I wonder , roughly, how much of battery life goes towards monitor?

Say, on average T42 can get 5 hr of battery life during some non graphic intensive work. What if at the same time monitor was turned off, how much more juice will this add to battery?

Once in a while I have to monitor some processes/real time data. For that, I need a monitor only when I take a peek at it. The rest of the time it can be turned off.

Thanks!

[bhtooefr]

I can't answer in even a ThinkPad specific context, but I CAN answer.

On my Dell, I was running speech recognition software, AI software, and speech synthesis software all at the same time, and it had the CPU at 100% all the time. The screen was down the whole time, and it lasted about 1:30.

When I'm playing games, it gets about 1:30 as well, but that's with the screen up. However, I'm not always pegging the CPU in that case (but, I'm pegging the integrated graphics, and hitting the RAM harder).

[gcchatel]

How about you run a test, I'd be curious to know. Just run the same application with the monitor on with a full battery till it dies and then with the monitor off.

[sugo]

Download mobilemeter. Run the laptop on battery. Note down the power wattage. Now hit Fn F3, wait for a minute and turn the LCD back on. Look at the graph again. The difference is approximately the power used by the screen. Some of the difference may come from the graphics card though.

[emorphien]

Pretty easy to find out, hook up an external monitor and disable the main display on the laptop. The screen is a huge battery eater though, it should be an appreciable difference.

[dimon]

I have tested this on X32 with 12" screen. With nothing scpecial running on monitor and few windows open discharge rate was 10w. After monitor was truned off discharge rate was 6w... 4w diff...

Full capacity of my 6 cell battery is 53w. So If I were to continue running with same windows open:
- with monitor I would get 5.3 hours
- and w/o it I would get 8.8 hours.

Not too bad at all...

Thanks all, you are great group of people. Nice to have a community of enthusiasts.

[fbrdphreak]

I have tested this on X32 with 12" screen. With nothing scpecial running on monitor and few windows open discharge rate was 10w. After monitor was truned off discharge rate was 6w... 4w diff...

Full capacity of my 6 cell battery is 53w. So If I were to continue running with same windows open:
- with monitor I would get 5.3 hours
- and w/o it I would get 8.8 hours.

Not too bad at all...

Thanks all, you are great group of people. Nice to have a community of enthusiasts.

Thanks for the info. This will be different with the T-series tho, as they use different screens. Also, 15" SXGA+ & UXGA use Flexview (or IPS screens) that draw a good deal more power. I will contact my IBM guy and see if I can find out (technically he's my Lenovo guy now :p)