laptops' power consumption

I am interested in getting a laptop because of their low power consumptions. The problem is, I am seeing numbers ranging from 10-75 watts, with no specific models quoted anywhere. I am looking at getting a Dell notebook, and am specifically eyeing the 9300. I need low power consumption, but my display needs to be relatively large.

Does anyone know what the power consumption is, in watts, for the various Dell laptop computers? Like I mentioned above, I am most interested in the 9300, but would like other numbers to compare it to. I am really in dire need of this information, as I expect to be paying upwards of 40cents per kwh when I move to Japan later this year.

.40 cents per kwh?!?! If I had that I'd pay more for electricity than rent! Wow...although I'm not sure on specifics, I can tell ya you MUST get a celeron m or P-M.


Here is a way to try to guess.....dells 53wh battery can give power up to 3.4 hours on the 9300 (which is probably idling and doing nothing). This would make it about 15 watts...now my guess is under normal use it would be 2-2.5 hours...so that's 25 watts....and under heavy use, 1.5...and that's being hard....which makes about 33 watts.
*note* your gonna lose power from converting the AC-DC...I'm not sure how much though, it's probably very small

Yeah, I had been planning on building a PC with a Pentium M for awhile. After I looked at all the components I'd have to lug half way across the world... well, I gave up on the idea. I tried looking at the battery consumption the same way you explained. That definitely does give me a ballpark estimate. I didn't however think about the loss between AC and DC. I am guessing the worst case scenario is that it is only half efficient, so that I am looking at a power consumption of 20-60 watts. Too bad I don't have a watt meter.

Does anyone on this board know off hand what the efficiencies of laptops are? Specifically, the efficiency of converting ac-dc (or vise versa... never can remember the difference), and the efficiency of their power supplies. PCs are getting really efficient with their PSUs, and I would hope that laptops are too.

I'd say it's around 90%+ efficient, it's not bad but it's not perfect either.

I think the the 9300 consumes at max 72watts or 89watts. The best way to figure max draw is to just take the amps and volts and getting the watts from that because Charging the battery is the max draw. When you completely drain the battery you'll be sucking 100% of what the power brick was designed to deliever.

My Asus sucks 65watts max on average is uses 15watts and gaming (HL2) it draw about 50watts.

At max draw this things sucks less than 5x my desktop/monitor at idle.

I have EXACT NUMBERS Reported by Centrino Hardware Control


The minimum wattage consumption I have seen on my laptop with the screen down and the processor undervolted and the gpu underclocked is 20 watts. Turning the screen completelly off will reduce it another 5 watts but then your laptop is only really good for playing music.


The absolute MAXIMUM POWER CONSUMPTION (except for burning CD's) I have ever seen on my laptop is 45 Watts (and that was with the cpu overclocked 30% and the GPU overclocked 40% Also with the cpu being voltmodded all runing 3d mark 05.


an average user will have their laptop running at about 30 watts or 2.5 hours with an 80watthour battery.


This is of course with the geforce 6800 GPU which consumes a substantial amount of power but what else can you expect of a mobile card that has desktop performance? If you get the x300 instead of the 6800 the power consumption should be around 17-22 watts for normal use...


the inspiron 6000 consumes about 20 watts at normal use.


you can expect 10-15 watts for ULV systems
~20-25 watts for midrange systems
~25-35 watts for HIGH END systems

of course that's only for Turion and pentium-m systems

DOUBLE THOSE NUMBERS FOR PENTIUM 4 SYSTEMS or multiply by 3/2 For NON TURION AMD SYSTEMS.

Bigger screens normally consume a couple more watts than smaller screens...






Remember when your battery gets low you can always go down to the local coffie shop and get some coffie for like $2 and then charge up your laptop while you are there...



just remember that a standard DESTOP CRT Consumes MORE than 90 watts and a standard desktop computer system can consume 200 watts or more.

Thanks to everyone for the great responses. I want to especially thank ozzlo for the in depth numbers that he posted. Now I just have to play the waiting game with Dell... haha.