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Compatible part needed for 4407-BESK4H

My laptop's main board model is EAL50 and a local repairer confirms the fault is the voltage regulator with part number 4407-BESK4H but that part is not listed anywhere so I can't get a replacement or any details to help work out what would be a valid alternative.
No replacement main board is available either so i need to fix this one.
Where do I look to find what part I need?

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  • brianlowe Apr 24, 2008

    I wanted to avoid dismantling the machine again until I had the required part, but I guess its necessary...

    Pic1 shows the main board with the parts' location boxed (top left of image).

    Pic 2 is as close and clear as my camera gets, but the stamp is still not visible.

    The parts are DIL 8 pin chips about 6mm long and 5mm wide. There are 2 of them (I didn't realise and don't which is faulty so I guess I'll be replacing both :(

    There is not much room for numbers. There is a logo (see pic 3) and 4407 on the top line then BESK4H on the line below. These 2 lines of print fill the top surface of the chip.

    So, anyone know what these chips are and what I can replace them with?

  • wpagot Jan 18, 2009

    I have a power-dead HP Pavillion laptop with two voltage regulators. 4407-CA714U Mine are working and they take in 18.68 volts and output 18.5 volts. You could try bypassing yours with an external regulated power supply set to 18.5 volts and see if that fixes your problem.

  • Anonymous May 13, 2009

    i have the same problem whit my acer 3023

    Anyone can find the component!


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This is AO4407. You can replace it by any 30V P-Channel MOSFET, for example FDS4435 or other.

Posted on Jan 06, 2010

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The regulator is not likely to be unique to the laptop, but that number doesn't mean much. Can you post a picture of the part or list the specific numbers on the part itself?

Posted on Apr 24, 2008

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