Hi Michael

The fact that the power supply LED dims on connecting the lap top is not a good sign.
It means the laptop is drawing a lot of current at least at start up ,or the power supply has lost it ability to supply enough current.
The only quick way to try is substitution of the psu.
Or to check the current drawn by the laptop with a multi meter in series with the supply. not easy, to see if it exceeds the power supplies current rating.
It may be easier to check for voltage drop across the connection (parallel) test.
If this is excessive that would also indicate high current.
If you feel it is the laptop drawing to much current. You could try removing some drives etc from their bays also any connected usb devices of course.
Good luck
Mike

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