Foxconn G9657MA

[eccerr0r]

OST

I used one of my fake nichicons to verify that I seem to have four dead OST caps connected in parallel on my other remaining working PCIe S775 board.

My Foxconn board has the weirdest mixture: Chemicon KZG, OST, Lelon, Rubycon MBZ, and some others I can't identify. The OSTs seem to have all bulged, as well as the KZGs. I wonder if the Rubycons are fake, though they appear to not be bulged.

I stuck one of my fake Nichicons in parallel with the suspect OSTs (I used a 3300uF, and the dead OSTs appear to be four 1000uF's) and it seems to have restored operation to the board. I replaced two of the suspect OSTs, though it's better it still isn't working perfectly. Now I need to replace a few more of these OSTs, just that replacing caps on this board sucks. I don't know when I'll get to swapping the KZGs but my 'scope seems to imply they're still mostly working.

The two OSTs I removed so far are around 5 ohms or more ESR.

It's Only Shitty Technology!

OST

[Wester547]

Re: Foxconn G9657MA

Are those the same "16V" "Nichicons" which outgassed after you applied +12V to them, just after their leakage current went through the roof, earlier this year?

What I noticed about those from your images is that the sleeves on those look unusually thick. It's as though those sleeves are sleeved over another cap sleeve - perhaps the real OEM of those counterfeit Nichicons. Sacons maybe? Would sure be interesting to "disassemble" them... if all the OSTs bulged, it's no surprise they measure around 5 ohms (although they could still look pristine and be open). If some of the KZGs bulged, surely the rest aren't far behind (and may already be out of spec)... the Lelon aren't good news either.

What makes you think the Rubycon MBZ are fake? If they have blue and gold sleeves, the sleeves on them are PVC. Black and white sleeves would indicate PET RoHS sleeves.

[eccerr0r]

Re: Foxconn G9657MA

Yeah it's those same fake 16V "Nichicons" that gassed at 12V. I haven't tossed them yet, but they did serve their purpose as sacrificial caps. These caps that I'm replacing are running at 1.3V.

Hmm. I might go ahead and disassemble one of those fake "nichicons".

Anyway yeah those OSTs were bulged but I couldn't detect their badness in circuit.

All of the KZGs bulged and leaked but the ripple still isn't too bad compared to the OSTs. I measured around 800mV ripple (ON A 1.3V line!) where the KZGs were around 50mV ripple... Not great but OK.

Ahh... I guess the PVC/PET is probably why. Maybe these are real authentic Rubycons after all. I was wondering why two caps of the same series have different sleeve colors.

[eccerr0r]

Re: Foxconn G9657MA

Off topic but for anyone interested
Fake "Nichicon" heat shrink removed.

[Wester547]

Re: Foxconn G9657MA

Thanks. Sorry, I didn't mean to have you disassemble one for nothing. I was thinking of the third one in your thread, actually (the one with the "thickest" sleeve), but you may have already used it for experimental purposes rather than sacrificial. Then again, it's a Teapo (or NTE?) in disguise rather Sacon, in accordance to the thread (although I suspect the real voltage is underneath the sleeve). No worries.

[eccerr0r]

Re: Foxconn G9657MA

Don't worry about it, the one I sacrificed was the one that vented, so no loss, all gain

I think they all have about the same thickness sleeve, it might appear thicker due to an optical illusion.

BTW, the one I cut open was a "type 3" but not the one pictured on the other thread. Just matched the rubber bung on the bottom.

(Now the question is whether it should be dissected further...)

[Wester547]

Re: Foxconn G9657MA

Oh, type 3 isn't Teapo in disguise then. Probably NTE.

Well, it looked thicker from the bottom. I suppose the attached image is what I was thinking of (the type of "counterfeit" which is not among your counterfeit Nichicons). If you look at the image full size, it's obvious the sleeve "appears" to be way too thick to be a production anomaly or optical illusion.

Are the other caps you can't identify Evercon by any chance?

[eccerr0r]

Re: Foxconn G9657MA

I need to see a bung of an Evercon, not sure what they look like. The evercons I found seems to have a 3-section vent but the ones I have are 4-section... no idea.

[Wester547]

Re: Foxconn G9657MA

Evercon/GSC/Sacon are known to use the following vent stamps, bearing no semblance of consistency:

Cross-hatch vent (+).
Y-shaped vent.
Honeycomb vent (AKA Jamicon).
Sanyo style vent (overlapping K).

[kc8adu]

Re: Foxconn G9657MA

first step is replace all ost and lelon.
they were junk new and they are not a fine wine that gets better with time.

[eccerr0r]

Re: Foxconn G9657MA

Drat one of the leads of the caps wont stick to the board anymore (dang those buried pads!), I must have pulled out a via or perhaps needs solder on the topside of the board. So I had to put a jumper to connect GND of that new cap... Oh well. The board with three new caps works much better than before now - the board is finally usable once more, boots and runs Linux again. Glad I don't need to buy another board to replace this board.

I only replaced 3 of the OST 1000uF 6.3V caps. I should go after the other ones but don't want to damage the board any more than I have to. I didn't check the ripple on the Lelons because they weren't bulged, I suppose I should have, maybe some other time...

I need to get some real rosin flux, the flux I have doesn't seem to work as well as it should...