For those that swear by KZG... :(

[Topcat]

AMD motherboard out of a HP. All the 2200uF 6.3v caps failed. The 1500uF 16v caps appeared OK physically, and checked within tolerance on the ESR meter. I replaced all with MCZ's, and all is right in the world.

[Shroomie]

Re: For those that swear by KZG...

Can we assume, or at least hope it was the fault of the PSU?

[kc8adu]

Re: For those that swear by KZG...

i am starting to see the same pattern tc
got an emachines with kzg blown in the vrm.vrm input caps are fine as is the psu.
i saw another with only 1 of the kzg lifted up off the board.
at least i dont use kzg for recapping....

[UraBahn]

Re: For those that swear by KZG...

Perhaps Chemi-con is overfilling those KZG, a la Nichicon HM/HN? Or maybe KZG weren't the ideal caps to use in that particular application?

I hope this is just a temporary QC glitch. Hopefully no other UCC/NCC series are affected. (Hey, every good company has to have their share of turkeys: Nichicon had HM/HN, and now UCC/NCC has KZG...)

In any case I guess I'll have to stick to my Ruby MBZ and Nichcon PL/PM for just a while longer.

[tiresias]

Re: For those that swear by KZG...

Great find Topcat... it would be unfortunate if UCC caps were to start getting unreliable too; the list of truly "never bad" low-ESR cap brands would get shorter still. Are we now down to Rubycon, Panasonic and Sanyo only?

The VRM on my wife's motherboard (by MSI) is packed with those KZG creatures... I'll be sure to inspect it later today just in case.

[Spacedye69]

Re: For those that swear by KZG...

My Compaq ASUS board has KZG also. With Teapo in the psu!

[gonzo0815]

Re: For those that swear by KZG...

I think it is a temp related issue. Those KZG are 2000h @105°c rated. So no very long endurance if temp is high. Considering the usuall bad vented and close HP & Compaq cases, the usually hot AMD proz and HSF, i can immagine, what the caps have killed. The VRM inout caps are usually KZE, wich is the long endurance series, but slightly higher esr. This is at least the pattern what i have seen on those KZG, basically based upon the post of this forum (e.g. Trodas DFI problem, again no vents, high heat ....).

May be we see the board coming back in several years, as the MCZ are 2000h rated too. But, as i used them on a regular basis, i hope there is a miracle wich would let those MCZ survive for ever. ;-)

[yanz]

Re: For those that swear by KZG...

i have some suspicious kzg caps with ugly quality of case/jacket i send to willawake for esr test, including the tmz ones i never heard of officially from ucc website.

for now i will only use two time more expensive sanyo wg/wx, panny fj and ruby mbz. at least they are good looking and slick

the board that was recapped by me from a year ago is still functioning fine. but i take the caution. kzg seems to hate heat and bad psu.

[Neo2_000]

Re: For those that swear by KZG...

Just worked an MS6368. About 6 KZG's looked like those in your photos.

[yanz]

Re: For those that swear by KZG...

TC and Neo, what is the psu? What cap(s) does it use?

[Topcat]

Re: For those that swear by KZG...

More KZG nightmares..... This is a Gigabyte dual Tualatin P3 board (forgot the model off the top of my head), running on a Zippy PSU (PSU is just fine). All the KZG's are popped.









I'm seeing more and more of these, so I think its safe to assume that the KZG line is declared an unworthy brand.

Definitely avoid using these in your recapping!

[tvtech]

Re: For those that swear by KZG...

Yep these caps are crap,have seen many of these caps bad in televison sets from the early 90's and up except the early 90's ones liked to bleed all over the board in thier OLD age and rot the traces away and the set would be doa.Now I have seen these these used in the newer HDTV's in the smps and digital boards along with the other famous brands of crap caps.Most i replace are only a few years old.It is ashame because these caps were considered to be good quality not long ago.Also being in the tv business I also work on computers so I have S-canned numerous power supplys for bad capacitors and recapped many mobo's.I didnt see many bad nippon capacitors until recently in computers.These forsaken caps have also been found in other small equipment such as routers,monitors,power supplys,car stereos.

[gonzo0815]

Re: For those that swear by KZG...

Well, i suppose that the KZG line realy does not like heat. At least for me there is somhow a pattern of heat related failure. Or in other word, the stated lifetime is with not mutch tolerance at higher temps. Thus i would not use it in anything they could getting hot. I am very happy to find them in a psu despite that. But usually in PSu`S there is more likely the KZE line used, as they are way more suited for that purpose, if no the lowest ESR is required. The lifetime is stated with 2000h @105°c for KZG, that is not mutch if the temp is high. IMHO most TV and similar equipment are very bad ventilated and are running realy hot. If an manufacturer decides to use KZG line there, i think the failure is preprogramed. Any way, i agree, that up to now there is enough evidence foe me, to avoid KZG`s if possible. I personally have always prefered Rubycon MCZ for lowest ESR and Panasonic FM for endurance and low ESR.

[yanz]

Re: For those that swear by KZG...

ok guys, expect to see bad news from me in the future because i was intensively using the kzg's on my recapping. the oldest one was from 12-14 months ago. they are still fine though. for comparison i use mbz and fc intensively too.

so, i put a great concern on this issue. now i stop at all using the kzg but i'll wait for any coming reports of failing kzg, coz i know some mobo manufacturer are still seriously using kzg in their top line products and kzg could be another fuhjyyu for us in the future.

another chemicon products like lxz, ky, i don't have any problem and have no doubt with them. now i get in my hands some kzj and they're among the best but are 2000hr caps too. soon i will use and test them and i'll see what happen after 1 year from now. due to this kzg issue i'm not hoping that much from this kzj, better be safe than sorry. fortunately i have plenty of choices in caps series i can use.

This is a Gigabyte dual Tualatin P3 board (forgot the model off the top of my head), running on a Zippy PSU (PSU is just fine). All the KZG's are popped.

so it's very unlikely that the psu is the problem. ironically zippy uses chemicon capacitors on their psu (iirc)

[PeteS in CA]

Re: For those that swear by KZG...

Concur with gonzo (and trodas may have run into KZG--heat issues a year or so ago). I think 2000-hour ultra-low Z parts - e.g. KZG, HM, HN - have less margin in hot locations. Rubycon 2000-hour parts seem not to be having problems (other than terrible availability). I wonder if it's because R'con has been a leader in developing that electrolyte technology. In Nichicon and UCC (NCC) the HE, KY, and KZE series seem to do better (KZH might also).

[toastygoodness]

Re: For those that swear by KZG...

I think it is a heat problem because all of my computers have KZGs, but one computer did happen to have one bulge slightly. It was running with those hot hot Prescotts. The others were AMDs and cooled well (enermax psu, sanyo denki fans, gigabyte heatsinks).

[kc8adu]

Re: For those that swear by KZG...

just got a evilmachines in with a row of blown kzg.
oh and tc that 6vtxd has another surprise!
the stink when you desolder those choyo's.
i have several of those boards and all had leaky stinky choyo's.
i added isa slots to all of mine too.

[gg1978]

Re: For those that swear by KZG...

I'm starting to be more sure that at least some of these are fakes. I've had more than a few HP motherboards lose their caps in the VRM section that looked like UCC LXY. Upon closer examination, there are some "naked eye" differences.


For one thing, look at the "shield" logo by the series designator. On a blown LXY from a late '00 HP Pavilion SOcket A board, there is a dot in the center of the shield logo, while a KZG from a dead MSI Nforce 4 board has no dot.

ALso, the KZG that appears to be real has relatively shallow relief for the tristar pattern on the top of the cap.. The "fake" LXY has significantly deeper cuts, and appear to be a little wider too..


Also, the font for the temperature designation is different.. The most obvious difference is the "0" in 105 C. The real UCC has a relatively short and wide 0, while the fake has a skinny taller 0. There are other differences in the font, but that's the most obvious. If you have the two side by side, there's no mistaking them.


One more difference i've seen is that the real ones have the aluminum case relatively "shiny" if held up to the light, while the fakes are more "dull" looking.

[linuxguru]

Re: For those that swear by KZG...

> there is a dot in the center of the shield logo, while a KZG from a dead MSI Nforce 4 board has no dot.

Not a reliable indicator - I have never seen a dot in the center of the crown logo, and I have plenty of good LXZs in front of me.

> KZG that appears to be real has relatively shallow relief for the tristar pattern on the top of the cap.. The "fake" LXY has significantly deeper cuts, and appear to be a little wider too..

Yup, I noticed this on a suspect KMG also. The vent cuts are wider and deeper, like they've been stamped. The real ones look much finer, with barely any signs of indentation.

> The real UCC has a relatively short and wide 0, while the fake has a skinny taller 0.

Not reliable - I have two good LXZs in different values here. One has a skinny 0 and the other has a fat 0, both in white. My guess is that it depends on the calibration of the jet printer at the time of manufacture.

> the real ones have the aluminum case relatively "shiny" if held up to the light, while the fakes are more "dull" looking.

Yes, this is accurate - the real ones have a mirror-like aluminium finish (sometimes stained by atmospheric oxidation, but still very smooth). The suspect fakes have a duller matt finish.

Check out the rubber plugs at the bottom as well. All the good ones I've seen (LXZ, LXF) have a wide channel between the leads, with a small raised triangle mark at the center of the channel. The fakes either don't use rubber plugs, or have rubber plugs with a different pattern and with the triangle missing.

[linuxguru]

Re: For those that swear by KZG...

> I have never seen a dot in the center of the crown logo, and I have plenty of good LXZs in front of me.

Original UCCs don't have a dot in the shield, but the ones made by Korean licensee Samyoung have a dot.These are also known to fail more frequently than the originals.

Samyoungs are usually clearly marked with the legend 'Samyoung', except for the very small cans, which have no space for the legend. Hence the dot in the logo. Samyoung is not fake, just a lower-quality licensee.