# [SOLVED] Charging/running laptop from car



## shatteredzman (Oct 22, 2006)

I am looking into getting a DC to AC inverter to run my laptop from my car and I was wondering what wattage I should be looking for. What I'm doing is plugging the charger into the inverter and running the laptop off my car battery. 
I tried a 100 watt converter but every time I do something like run a 3d game on the laptop( not while driving of course) the inverter shuts itself off and restarts and the laptop screen goes dim for a second because its switching to its battery for half a second. I thought it might be my car but I tried it in a brand new car and it still did the same thing so I dont think I have enough watts.
So would 150 watts do it? 150 watts seems to be the highest newegg.com has besides one single item that is 300 watts but I dont want to spend extra money if I dont need to.


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## V0lt (Sep 14, 2002)

*Re: Charging/running laptop from car*

What's the wattage of the power supply for the laptop? As far as I know, that figure is the absolute max that it should ever draw.


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## shatteredzman (Oct 22, 2006)

*Re: Charging/running laptop from car*

Hmm it doesnt give watts but it does give amps and voltage and to get the watts I think its "Watts = Amps x Volts". The AC outlet is putting out 110 volts so that means 187 watts I think. So I guess now the question is if 150 watts will be enough to keep the inverter from restarting itself.


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## V0lt (Sep 14, 2002)

*Re: Charging/running laptop from car*

Sort of unusual that it wouldn't have it listed, but it seems about right- my old laptop's supply has a max output of 70 watts, ~3.5 amps * 20V

I'm not sure how forgiving those inverters are, but if it's any consolation, I see models > 200 watts all the time, and they're really really cheap. But I've run my Acer laptop with a 150-watt (maybe it's 175?) without a hitch, and it tends to be very power hungry.


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## shatteredzman (Oct 22, 2006)

*Re: Charging/running laptop from car*

Well you know what I was looking at the imput for the charger the output is 15 volts and 8 amps and thats only 120 watts. Thanks for the help, looks like I just needed a little bit of advice and a push in the right direction.


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## shatteredzman (Oct 22, 2006)

*Re: Charging/running laptop from car*

Alright I purchased this.
http://www.newegg.com/Product/Product.asp?item=N82E16812120305
150 watt and 300 watt peak power..whatever that is. It seems to run fine, no restarts, no power dips, but it sure does drain my car battery if I dont have the car running! Consider the problem solved. Thank you.


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