Pulled some industrial P4 S478 motherboards out of storage for inspection and testing.
First in an Advantech AIMB-742. Attempting to power it up, it had POST codes of 13-12. It also had a stuck reset line and soft power is also stuck on.
It does have a missing inductor (L23) on the back of the board and some minor scratches. None of the caps appear leaky, although that's no guarantee. I'll probably remove and test some of them to be safe.
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I have a second Advantech AIMB-742 board which has a bunch of corrosion on it. The chokes are all rusty and there is further corrosion near the rear sockets, including on an IC sandwiched next to the PS/2 port. It also has a bunch of leaky caps. Not looking forward to trying to repair this one.
On the upside, it has L23 inductor that the other board is missing. So I'll probably transplant it to the other board.
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Finally a DFI ITOX G4E620-N. It's in decently good shape except for a bunch of nasty looking caps. I'm going to look into replacing these with polymer caps. Haven't done that before, so I'll need to research what would be appropriate values.
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