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Thread: Dead Resistor

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    Default Dead Resistor

    Hey Everyone,

    Friend of mine brought over his rig yesterday, was having boot issues.

    I removed his psu, opened'er up and this is what I found:



    It's a crappy Purepower, so no biggie for him. Is there anything in particular that would cause a resistor to go other than old age?

    Thanks

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    IMO this resistor is a dummy load. It's hot.
    It's been a hard day's night and I've been working like a dog.

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    Thanks Travis,

    Could you explain a bit further?

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    See attachment. R62~R66 are dummy loads.
    Switch-Mode Power Supplies need a minimum load current to work normally. These resistors are used to generate that current. The heat disspation on each resistor is determined by Ohm's law.
    If only the resistor is damaged, simply replace it with an 1W resistor with same resistance value.
    It's been a hard day's night and I've been working like a dog.

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    Many Thanks

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    Resistor doesn't look dead to me, it's just the glue that's been cooked by the heat coming off it.

    Your friend's boot issues are probably caused by something else (like failing capacitors)

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    Capacitors were find not a one bulging.

    I used the sniff test to figure out where the *burnt* smell was coming from, and the resistor *smelled* like the culprit.

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    Quote Originally Posted by Sphere View Post
    Capacitors were find not a one bulging.

    I used the sniff test to figure out where the *burnt* smell was coming from, and the resistor *smelled* like the culprit.
    A cooked resistor doesn't look nice and pink like that, and the glue right next to it looks decidedly burnt.

    And remember: "All bulging caps have failed, but not all failed caps bulge" In your case they may have just dried out, or haven't bulged noticeably *yet*

    What brand are the caps and how old is the PSU?

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