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Dead BXcel PC100 / PCChips M726

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First post, by Vaylo

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Dears,

Currently, I have a completely dead M726 on my desk. It does not post, produce any beeps, or show any video signal—nothing. I tested it with multiple working PSUs, CPUs, GPUs, and RAM modules. I measured the presence of voltages that I know of (on ISA slots) and also tested for shorts on the AT connector—everything appears to be okay. The CPU fan (connected to mobo) spins normally.

One oddity I noticed is a Schottky rectifier diode highlighted in the picture. While it's powered off but still in the circuit, I can measure continuity between each of its legs in both directions and the same between ground and each leg in both directions. Is it safe to say that at least the Schottky diode is shorted?

Thanks.

schottky.jpg

Reply 1 of 1, by PC@LIVE

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Recently, I purchased and brought back into operation a BXCEL motherboard, I don't know which model, there are two, from memory it seems like M729 and M726, I only encountered a contact problem in Slot1, otherwise the card works well.
Before removing that component, I would make some measurements, with a tester, first on the power supply connector, in OHM between ground and the line contacts (+5 +12), then if they are ok, I would measure the voltage on the pins of the Mosfets (or regulators ), write down what you find, and write it here.

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