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    AC Adapter Question About Volts

    Discussion in 'Hardware Components and Aftermarket Upgrades' started by Joe E. Gee, Apr 23, 2009.

  1. Joe E. Gee

    Joe E. Gee Newbie

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    Hello Everyone!

    I found an HP laptop that I was going to purchase, but I wanted to be able to use my old AC adapters from my IBM ThinkPad. It would be nice to have a couple of extra power adapters in key locations to avoid moving a single adapter around.

    The HP laptop AC adapter volt output is 19.0 V dc.

    The IBM/Lenovo adapters I have produce 20 V dc.

    The plugs/connections look identical.

    Question: Is the one volt additional output much of a risk?

    The standard answer from a manufacturer would be to not use the 20 V adapters, but how much of a risk would I assume by occassionally using an adapter that creates 1 additional volt?

    Thanks for all your help and keep the good work!

    Joe
     
    Joe E. Gee, Apr 23, 2009
    #1
  2. K-TRON

    K-TRON Hi, I'm Jimmy Diesel ^_^

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    The power adaptor may not even work in your system.
    On newer systems, HP/Dell they all have impedance matching technology built into the motherboard. This means that the system will reject a power supply if it was not designed to work with the system. If your laptops are over 3 years old, you shouldnt have any problem.
    1V is not the end of the world, more than likely the motherboard takes the input current and brings it down to 12V for the system to run.

    K-TRON
     
    K-TRON, Apr 23, 2009
    #2
  3. SpeedyMods

    SpeedyMods Notebook Deity

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    Not only will it likely not even fit, I wouldn't take the chance personally. There is too much of a risk with extra voltage.

    Greg
     
    SpeedyMods, Apr 23, 2009
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  4. sironin

    sironin Notebook Guru

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    Keep in mind you'll also want to pay attention to amps. 1 volt isn't a huge difference but a couple of amps difference could cause significant damage.
     
    sironin, Apr 23, 2009
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  5. Commander Wolf

    Commander Wolf can i haz broadwell?

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    The amount of current the adapter can output only becomes a problem if the laptop is pulling more power than the PSU can supply, not the other way around. The adapter will only feed the laptop as much current as it needs, so a 20V, 5A adapter will work perfectly with a 20V, 1A laptop. A 20V 1A adapter will likely burn out trying to feed a 20V, 5A laptop.
     
    Commander Wolf, Apr 24, 2009
    #5
  6. lengendnr

    lengendnr Notebook Geek

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    I tried different adapters for my old compaq armada laptops..

    Basically as long the plug can fit, it will work..

    Not sure about newer system though..
     
    lengendnr, Apr 24, 2009
    #6