Post help identifying capacitors here

[MrWizzard]

Re: Post help identifying capacitors here

Nippon Chemicon KY series is pretty much a direct cross.

Thanks from the first post this is what I ordered already. Hopefully they will work.

https://www.digikey.com/en/products/...6HwRTXu1qeNSWT

[momaka]

Re: Post help identifying capacitors here

MrWizzard - a couple questions - what was the power supply powering the system seeing as how they are on the +12V VRM input of the CPU buck regulator? Did it run 24/7 for several years? I find it slightly worrying hearing about Nichicon’s HD series failing like that even though going by the “Z4” date codes (the 4th week of December, 2002, according to the JIS C 5101 standard) they are over 20 years old now and were in storage for years (not particularly great, especially for water base capacitors such as the HD series).

+1

O/P should definitely check out (and maybe show us) the power supply that was used. While it is possible that the caps "depolarized" if they sat too long in storage, I also agree that the PSU could be part of the reason they went - especially if it's not a new PSU but rather original with the system.

BTW, haven't seen you for a while, Wester547, but good to see you're back.

Chemi-con KZE and Rubycon ZL should be a direct cross.

Other alternatives are:
Rubycon ZLH, ZLQ, ZLK, and ZLG series
Panasonic FR, FM, and FS series
United Chemicon KZH and KZM series
Nichicon HW and HV series. HE will likely work OK too, even though they are not quite up to spec as the HD series (on the other hand, HE is more durable.)

Nippon Chemicon KY series is pretty much a direct cross.

UCC KY is slightly lower spec (in terms of ESR and RC) compared to Nichicon HD / Ruby ZL / UCC KZE... but they've been proven to be very reliable and should work too. Just may not filter as much noise due to slightly higher ESR.

For what it's worth, UCC KY is a direct cross with Nichicon HE, Panasonic FK, and Rubycon YXG.

I usually go with whatever is cheapest on Digikey or Mouser... and Rubycon ZLH seems to be that series currently. Years ago, Mouser used to have Nichicon HD and UCC KZE very cheap (much cheaper than other series.)

I suppose for 1 or 2 caps for a motherboard, it doesn't really matter. But when buying for lots of stuff, it does "save" a few $ here and there, which I can then "re-use" for buying other caps and parts.

BTW, MrWizzard, consider replacing all of the 16V 1000 uF Nichicon HD caps at this point, since it's hard to say whether they blew from a possibly questionable PSU or just old age. Nichicon HD series are generally pretty reliable... though they are a little more "sensitive" (particularly with heat) compared to other series from Nichicon. Their next lower step series (HE) and higher step (HC) series are both more reliable for whatever reason.

While buying caps, also consider getting more caps for the rest of the motherboard. Better yet, start a new thread, post some pictures of the motherboard, and list what capacitors it has. Being an Intel i845 series, it probably doesn't have many other large caps, aside from the ones around the CPU. Look out for any brown caps with label "KZG", though - particularly if they are 6.3V 3300 uF. These are known to go bad too. Nichicon HM and HN series starting with date codes of H01_ _, H02_ _, H03_ _, and H04_ _ are also known to have reliability issues and should be replaced.
Anything 330 uF and up in capacitance is usually OK to leave as-is... though sometimes Intel likes to put some small caps around hot linear regulators (particularly in the area close to the AGP slot between the NB and SB). These may be bad too if you see the board darkened around the regulators and if these caps were in the vicinity.

[Wester547]

Re: Post help identifying capacitors here

MrWizzard - a couple questions - what was the power supply powering the system seeing as how they are on the +12V VRM input of the CPU buck regulator? Did it run 24/7 for several years? I find it slightly worrying hearing about Nichicon's HD series failing like that even though going by the “Z4” date codes (the 4th week of December, 2002, according to the JIS C 5101 standard) they are over 20 years old now and were in storage for years (not particularly great, especially for water base capacitors such as the HD series). Chemi-con KZE and Rubycon ZL should be a direct cross.

[PeteS in CA]

Re: Post help identifying capacitors here

...

Here is a picture of them. I see the letters HD Z4 1000 16V and that is it. Does not have the writing on them that other capacitors have to identify them. Can someone help tell me what I should replace the bad ones with?

Thanks

Nippon Chemicon KY series is pretty much a direct cross.

[MrWizzard]

Re: Post help identifying capacitors here

Nichicon HD 1000uF 16V

Nichicon decided to discontinue a lot of parts, so get then while you can. Nichicon's datasheet doesn't have that value marked as "not recommended for new designs," but Digikey does. Rubycon ZL looks like a decent alternative if they do disappear.

Thanks for the advice and help!

[lti]

Re: Post help identifying capacitors here

Nichicon HD 1000uF 16V

Nichicon decided to discontinue a lot of parts, so get then while you can. Nichicon's datasheet doesn't have that value marked as "not recommended for new designs," but Digikey does. Rubycon ZL looks like a decent alternative if they do disappear.

[MrWizzard]

Re: Post help identifying capacitors here

Hello, new user here. Trying to find what capacitor to replace a couple capacitors that went bad today, heard a double pop at power on and found 2 that are bulging and were hotter than others. New to all of this, trying to teach myself how to do this rather than buy a new used MOBO.

The mobo is a Intel D845GEBV2. I tried searching the forum and only found 1 question about a different capacitor on this board.

Here is a picture of them. I see the letters HD Z4 1000 16V and that is it. Does not have the writing on them that other capacitors have to identify them. Can someone help tell me what I should replace the bad ones with?

Thanks

[failuresuccess]

Re: Post help identifying capacitors here

Awesome, thank you so much for your guidance!

[lti]

Re: Post help identifying capacitors here

Those will work, but the last two are a little expensive.

[failuresuccess]

Re: Post help identifying capacitors here

Hi Lti,

Thanks for the insights! The reason I was considering replacing the caps is that the motherboard over the past year has gotten more and more flaky to the point of no longer POSTing. I pulled all the hardware and tried booting with different cpus and memory with no luck and the PSU checks out.

That said do you have any concerns with the following caps?
68uf
https://www.mouser.com/ProductDetail/710-860010372005

22uf
https://www.mouser.com/ProductDetail/594-MAL203851229E3

2.2uf
https://www.mouser.com/ProductDetail...D225M050JA6AE3

[lti]

Re: Post help identifying capacitors here

Those blue Nichicon caps are VX series, but I've never seen a datasheet for the radial version (only axial). They're just plain 85°C caps, so specs don't really matter (especially since they're 30 years old and probably still good unless they're leaking). There are places where ESR can be too low, but that isn't likely on a motherboard like that.

If an unknown series of a known brand counts for this thread, I found a power supply with G-Luxon LM series caps. I don't know if they're actually bad, but that computer had some weird cold boot problems. I'd lean toward these just being general purpose caps, and I really don't want to recap this thing anyway. It has a buttload of tiny caps, mostly 1uF in a mix of 16V and 50V for some reason.

[failuresuccess]

Re: Post help identifying capacitors here

Hello all, I'm in the process of trying to restore a motherboard for a 1993 IBM PS/1. I'm looking to recap and so far they all appear to be Nichicon electrolytic caps. I believe they are 68uf 16V, 22uf 50V, and 2.2uf 50V. However, I can't figure out the model number is to get their exact specs. Please see the attached image and any advice would be much appreciated.

[jiroy]

Re: Post help identifying capacitors here

Thank you very much

Welcome friend ; I left the choice of online order location to you as convenient . Otherwise , do tell .

[kalemaroni]

Re: Post help identifying capacitors here

That a code for the manufacturer series . No , not any package , this is a SMD Capacitor and not TH one (through hole) .

Thank you very much

[jiroy]

Re: Post help identifying capacitors here

Thanks - and the 7H bit doesn't matter? Will any package do the job?

That a code for the manufacturer series . No , not any package , this is a SMD Capacitor and not TH one (through hole) .

[kalemaroni]

Re: Post help identifying capacitors here

It's 100 mF , 25 volts ...

Thanks - and the 7H bit doesn't matter? Will any package do the job?

[jiroy]

Re: Post help identifying capacitors here

Can someone identify this cap for me please?

It's 100 mF , 25 volts ...

[kalemaroni]

Re: Post help identifying capacitors here

Can someone identify this cap for me please?

[momaka]

Re: Post help identifying capacitors here

The question then, however. What's a good "low" ESR ? I've been told there can be such a thing as "too low" depending on the application. This particular cap sits on the output side, btw. (maybe this isn't the right section of the forum to discuss these details)

Well, for the output of PSUs, generally you want to avoid the lowest ESR series... but even then it depends on the PSU, or rather its design.

Discontinuous / flyback designs (you can distinguish those fairly easily, as they don't have an output toroid after the rectifier(s)) don't care about too low of an ESR. They may get a little more noisy (as in, audible noise and not necessarily electrical noise) with very low ESR caps. But apart from that, they would work fine.

Continuous designs, on the other hand (these you can identify by a large output toroid inductor after the rectifier(s)) can be a little more picky. So with those, it's better to avoid the lowest ESR series, unless the PSU uses such already.

Which brings us full circle back to your question: how would we know what kind of "low ESR" caps the PSU used if we can't identify them?
- IME, I just haven't seen any of the no-name manufacturers to offer very low ESR caps. At best, they might have something that resembles United Chemicon KY or Nichicon HE or Rubycon YXG (which would be considered "mid-grade" low ESR more or less)... but almost never, really. More often than not, a cheap manufacturer's "low ESR" series will be barely a notch better than general purpose series from the Japanese manufacturers. The "better" ones might be comparable to entry-level low ESR series like Rubycon YXJ, Nichicon PS/PM/PW, UCC LXY/LXV, and Panasonic FC.

So this is why I don't bother to look up obscure brands anymore. I just pick some caps anywhere between entry-level low ESR and "mid-grade" low ESR, and know that I will be pretty safe with that choice. If I feel experimental (or if it's a discontinuous/flyback design), I sometimes go with very low / ultra-low caps that I might have on hand... and even with those, I haven't had any issues. At worst, I've had one or two flyback-based PSUs just "whine" a little more when lightly-loaded or in standby mode.

[mach128x]

Re: Post help identifying capacitors here

If it's in a SMPS, it probably is (or should be) low ESR.
But don't worry about identifying it or finding a datasheet for it. I stopped bothering to look up obscure manufacturers a long time ago. In all cases, I just use a low ESR capacitor from a known good Japanese brand (like Panasonic, Rubycon, Nichicon, and United Chemicon.) Never had issues replacing these obscure brands by such. In fact, these no-name garbage caps are so bad, that sometimes I've used very old Japanese general purpose capacitors for a repair or two, and even those have lasted longer than the cheapo caps.

I understand your point.
True, my hope was to find the original ESR rating, to find something in the same ballpark.
I was going to replace it with a good quality one in any case, for sure.

The question then, however. What's a good "low" ESR ? I've been told there can be such a thing as "too low" depending on the application. This particular cap sits on the output side, btw. (maybe this isn't the right section of the forum to discuss these details)