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    Screen Goes Dark Sometimes After Plugging In Charger

    Discussion in 'Lenovo' started by Faustus, Jul 8, 2011.

  1. Faustus

    Faustus Notebook Enthusiast

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    Hello, I got my ThinkPad T420 two days ago and I'm finally done setting it up. I love it but I think something is wrong.

    Twice now, one last night on Windows while transferring files from old computer to new, and once again now on Ubuntu listening to music, the screen went almost black (could make out things barely) after plugging in the charger. This does not happen all of the time when I plug it in, only when the battery is low, or at least that's what I think. This time I know for sure the battery icon on Ubuntu was in the red and I think Windows had it fairly low as well. Both times the laptop was still functioning, for example music was still playing. Also the problem can be fixed by pressing Fn+F4 to put the computer to sleep and then starting it back up.

    Anyone know what's up with the laptop :confused: Driver issue? Battery issue? Display issue? Working as intended?!

    Edit: Reading around other forums and some older posts say that it could be a Power Mangement issue which does explain why it only happens on low battery. Checking my power management on Ubuntu and nothing of the sort...
     
    Faustus, Jul 8, 2011
    #1
  2. pkincy

    pkincy Notebook Evangelist

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    Normal.

    Only for a couple of seconds after plug in to AC. at least on my X220. My W520 is plugged in most of the time, so don't know on it.
     
    pkincy, Jul 8, 2011
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  3. Faustus

    Faustus Notebook Enthusiast

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    Really? I can't imagine this being practical though!

    Reading some more found this: Dell laptop screen goes black when charging with cord - Tech Support Forum

    Exact same scenario described. Would checking BIOS settings fix whatever is happening? Since it occurred both on Windows and Ubuntu it has to be something overlying, right? BIOS would solve that issue?

    EDIT: Speaking from a technical standpoint would the BIOS be the likely culprit? Looking at the Power settings in it I see that it's Mode/Scheme for AC is set to Maximim Performance. I'll give it a shot and see if it fixes the issue.
     
    Faustus, Jul 8, 2011
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  4. JohnsonDelBrat

    JohnsonDelBrat Notebook Evangelist

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    JohnsonDelBrat, Jul 9, 2011
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