Author Topic: MDD Capacitor leakage  (Read 848 times)

Offline Greystash

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MDD Capacitor leakage
« on: December 17, 2023, 03:45:39 PM »
I was just replacing the fans in my MDD PSU with quieter Noctua fans and noticed some suspicious looking capacitors. Is this evidence of leaking capacitors or something else? These are the only capacitors in the PSU that looked bad.

Offline aBc

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Re: MDD Capacitor leakage
« Reply #1 on: December 17, 2023, 04:04:40 PM »
Samsung or AcBel PSU?

And yes, they've "popped their tops".
You may notice all of them are Y-ed at the top to allow for such possible expansion...
whence they emit their preliminary death k-nell.



Usually, they'll dome like these discovered last night in a Quicksilver's PSU.
(Red dots on the domed / bulged ones. They're supposed to be flat on top.)

Or they may go straight to eruption, as evidenced with yours. Sorry.
But best that you've found it now, rather than later.

AND you can't really judge good or bad ones - by such mere appearance alone.
They can appear fine and still be failed or failing... 'specially them TEAPO caps.

Offline Greystash

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Re: MDD Capacitor leakage
« Reply #2 on: December 17, 2023, 04:17:15 PM »
Thanks aBc!
It's an AcBel PSU. It does still work fine apart from the occasional lock up when unplugging, plugging in USB devices, but I won't run it now that I know what the problem is!

I have a MDD to ATX PSU cable which I might use but I've read that most PSU's won't supply the continuous 5v required for deep sleep. Have you performed any of these conversions before? I might rec-cap it first instead.

Offline aBc

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Re: MDD Capacitor leakage
« Reply #3 on: December 17, 2023, 04:25:35 PM »
No ATX conversions here (yet).
But I have done a little PSU surgery before.

You might even just replace what appears to be bad (at first) and see how that goes.
(Once you get used to the old in & out routine.)

But there's always this... for some reference:
http://macos9lives.com/smforum/index.php/topic,4088.msg28011.html#msg28011

Offline Greystash

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Re: MDD Capacitor leakage
« Reply #4 on: December 17, 2023, 04:30:41 PM »
Thank you that's incredibly helpful!!

Offline ssp3

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Re: MDD Capacitor leakage
« Reply #5 on: December 17, 2023, 04:30:55 PM »
The brownish stuff looks like a dried out and slightly "baked" glue to me.
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