Hi,
Replacement capacitors have arrived and I've replaced the large one and the medium size one that was looking a bit dodgy on the top. Hasn't made any difference!
I've been swapping the good and bad DAC unit around just to confirm the problem:-
The good DAC unit allows the motherboard CPU fan to spin by shorting out the relevant switch pin connection. ALSO, when connecting the test bulb to the power supply from the DAC unit to the motherboard I get a strong light with NO flashing.
Swapping over to the faulty DAC, the CPU fan will not spin and checking the power supply with the bulb I get a pulsing light, almost on/off .
I'm getting convinced that somehow the DAC board is passing through some AC voltage to the motherboard - presumably indicating failure in some of the votage regulation side of the DAC ??
Re the 5 devices connected to the heatsink, 4 appear identical
CQ526 MBR 2045CTG
the fith, could be M50PO3HDLG CQ550 - very difficult to read?
Any thougths?
Regards
Alan C