Super User is a question and answer site for computer enthusiasts and power users. It's 100% free, no registration required.

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

I'm looking to buy a number of car power adapters to be used with some Dell laptops.

^ This is the item I am currently looking at.

Will it be able to power a Dell Lattitude E6500?

Looking at the power supply of the laptop, it states that it is a 90W-AC Adapter. The car adapter states that it is a 60W DC - AC Power Inverter.

Will this work? Do I need an DC-AC Power Inverter that is 90W or higher? I am nothing close to an electrician, please help me out.

Thank you.

share|improve this question
I recommend you to use an adapter of 90 W or higher. Preferably higher, so you will probably not have any problems with it. – petersohn May 18 '10 at 18:54
Just get an inverter that achieves enough power based on your specs... Should work fine. – nicorellius May 18 '10 at 22:21
up vote 3 down vote accepted

If your laptop is always in low-power mode then the 60W inverter may be enough for it. If you want to be certain that you don't burn the inverter out then you should get at least a 126 (90*1.4) watt inverter.

share|improve this answer

If you run a 90 watt laptop on a 60 watt power supply you risk overdrawing the power supply (early death for the charger) and also some chargers may run the laptop, but the battery won't charge. Targus and Kensington usually note that while their 60 watt chargers may spin up a laptop, they won't charge the battery for example.

share|improve this answer

Ideally, you would get a DC power adapter for your laptop, rather than converting from DC to AC, then back to DC again. But if you want to be able to plug in other devices, you should get an inverter that can handle at least 90W.

You could get the 60W adapter and try it, but you should first measure the AC adapter's draw under varying loads while plugged into the wall--for example, maxing out the screen's brightness and ripping a CD or DVD while the laptop is fully charged, vs. doing the same while the laptop is charging.

If you do end up getting the 60W inverter and you happen to overload it, the fuse in the inverter should blow. If the battery is already charged when you hook up the laptop, you might be fine. But if the battery is partly depleted and the AC adapter tries to charge it, you'll probably end up drawing more than 60W. A slightly annoying workaround would be to physically remove the battery when using the laptop in your car.

share|improve this answer

Your Answer


By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.