The box which is completely dead, only the lan LEDs.

Check the ohm values of the P5, not the voltages, so do not connect the psu.
On this picture you see three rows of ohm values of three motherboards.
Check whether one or more has a different value.
All values has been measured between the ground and the measure point.

http://jb8a8f8.com/support/index.php?attachments/dm800hd-fault-finder-pinout-ohms-2013-jpg.23/
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Doing nothing leads to nothing.

------------- Please note, for technical support -------------
Will be given here, or on the jb8a8f8 forum and I prefer it in English.
Johnny B.

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