HM HN, Dates for the bad boys?

[Behemot]

Re: HM HN, Dates for the bad boys?

I can confirm problems with 2005 HM's - just yesterday I was preparing bad boards for reselling for gold extraction, so I got the caps out. Full set of A0509 HM's 1500 uF/6,3 V is showing ~1950 uF on ESR Micro. So if that's true about the leakage, they are bad.

[Behemot]

Re: HM HN, Dates for the bad boys?

Well the only remaining source is old stock from eBay resellers but you have to tripple check for fakes…at least there is that buyer protection so you can even get your money back if they sell you shit

[momaka]

Re: HM HN, Dates for the bad boys?

The problem is that they (and others as well) are very hard to come by in my country.

This will soon follow around here as well since Rubycon has discontinued the MBZ and MCZ series. Likewise, Nichicon has discontinued the HM, HN, and HZ series. So what's left? United Chemicon KZJ and KZG - but we all know those are unreliable. So short of polymers, there isn't much else. I guess the best you can now get is Panasonic FM and FR and Rubycon ZLK and ZLG, with ZLJ and ZL and Chemicon KZE and Nichicon HD being right underneath them.

[UserXP]

Re: HM HN, Dates for the bad boys?

Well, if you read around badcaps.net, you will see that Rubycon isn't all problem-free either. In particular, their MCZ series are not very tolerant of high heat and will often bulge. Also, their MBZ series seem to have had a little "oopsie" too. Have a look in this thread:
https://www.badcaps.net/forum/showth...&highlight=mbz

LOL, having checked the link, it turned out that I've actually read that Topcat's article before, but it was quite a while ago, so I forgot. Thanks for the reference.
It was probably, like Topcat said, a bad batch or something. I have put MBZ caps on this S478 board of mine, their dates are from 2002 (the 6.3V, 3300uF ones), 2003 (the 16V, 1500uF ones) and 2005 (the 6.3V, 1000uF ones). Here is the board still working flawlessly every day.
No matter how good the electrolytic mixture is, the heat will always be its downfall, I guess. In general, I've never had problems with any of the Rubycons myself, so I still consider them to be highly reliable caps. The problem is that they (and others as well) are very hard to come by in my country.

[Behemot]

Re: HM HN, Dates for the bad boys?

I've tried to artifically heat the NB, it showed same behaviour - most likely bad BGA or die soldering. Will try to heat it with hot air gun and and add a fan on the heatsink, that's all I can do, otherwise it will go to electro-scrap.

[momaka]

Re: HM HN, Dates for the bad boys?

I remember that measuring the CPU VRM, all the caps together measured way more than their nominalxnumber of caps is. May be they are leaking? Should I try to replace them?

I can't say for sure. Pull a few and measure them out of circuit. If they aren't too high in capacitance, they are probably okay. If you have the caps, you might as well try and replace all of them. If it fixes your problem, perhaps they were going bad indeed.

[Behemot]

Re: HM HN, Dates for the bad boys?

I wouldn't doubt them but considering these reports…got Gigabyge GA-K8NF9 Ultra. Full of HM (or HN? don't remember now) made somewhen in 2005. There was reportedly one bad cap, replaced with some PoS from local store, I replaced it with some used Panasonic (FL IIRC). PSU was bloated, I've recapped it, but it ceased working - replaced with another recapped one. But board keeps behaving strangely - sometimes got 0x0000009c error, it often does not even POST. Different graphics - same behaviour. RAM after 24+ hours in Memtest86+ OK.

I remember that measuring the CPU VRM, all the caps together measured way more than their nominalxnumber of caps is. May be they are leaking? Should I try to replace them? Or just the nForce 4 is dying…

[momaka]

Re: HM HN, Dates for the bad boys?

Of all those Japanese capacitor manufactureres, I've never read anything bad about Rubycons, they seem to be a very reliable brand.

Well, if you read around badcaps.net, you will see that Rubycon isn't all problem-free either. In particular, their MCZ series are not very tolerant of high heat and will often bulge. Also, their MBZ series seem to have had a little "oopsie" too. Have a look in this thread:
https://www.badcaps.net/forum/showth...&highlight=mbz
Despite that, I still consider Rubycon high quality, though.

Now, some may argue that Panasonic is the best as it seems like they haven't had any failures with any series. And while that may as well be true, their series with lowest ESR are FL and FJ. But these aren't quite as low ESR as Nichicon HN/HZ or Rubycon MCZ/MFZ, so that's also to keep something in mind. Also, in my experience, some Panasonic caps (particularly FL) have had very soft rubber bungs on the bottom. Nothing wrong with that until you accidentally heat the cap just a little more when soldering/desoldering. And then the next thing you notice is the cap is leaking electrolyte from the bottom. This happened to me with a few Panasonic FLs I removed from some P4SD motherboards.

Therefore, I don't really consider Nichicon any worse than the above. Sure they did have problems with their 2001-2004 HM and HN series (and possibly HZ?) as well as some from 2005. But outside of that, they have had good history as reliable caps.

Chemicon is the same way too. Though it looks to me that they still haven't (and probably won't) fix their problems with their KZG and KZJ series (and possibly TMZ). But their other series are excellent! So I use Chemicon in repairs quite often too.

[UserXP]

Re: HM HN, Dates for the bad boys?

So, there are indeed various experinces with Nichicons, even the datecodes sometimes do not denote a stable/quality build. Of all those Japanese capacitor manufactureres, I've never read anything bad about Rubycons, they seem to be a very reliable brand.

It is amazing how many motherboards and their brands used these Nichicon series even though there were serious mistakes involved in their production, but MB makers still continued using them. I guess production costs are taken into account here, but it is simply a bad idea to design a solid and quality electronic equipment only to risk its destruction but putting some problematic capacitors on it.

[PeteS in CA]

Re: HM HN, Dates for the bad boys?

In an electrolytic capacitor, the electrolyte is a conductor. The capacitance depends on the surface area of the plates and the thickness of the dielectric, which is a layer of aluminum oxide on the anode foil. If the capacitance of those HZ caps has increased over time, that means the electrolyte has attacked and thinned the aluminum oxide layer. Not a good thing! That increases the capacitance and decreases the actual maximum voltage the part can handle.

[momaka]

Re: HM HN, Dates for the bad boys?

I guess it did depend on a particular production line or something, right?

It's possible.

I think this issue also possibly extends to the HZ series.
Last week, I dug up some severely bulged 6.3V 2200uF Nichicon HZ from my parts bin. These caps were pulled from various Xbox 360 motherboards, but they were all good at the time I pulled them. That was about a year ago, though.

Now check this out: the Nichicon HZ caps with datecodes H06 and newer (so 2006 and newer) are all fine. However, several of the H05's were bulged. Moreover, last time I used the MicroESR to check another parts bin of mine that also had various HZ caps, most of the 2200uF H05 HZs read 2300-2400 uF and some even higher. But not a single one lower.

Perhaps overfilled like the defective series from 2001-2004? I think so. Maybe not as badly, as Nichicon likely had figured out their mistakes by that time and were probably just "tweaking" their manfacturing process.

For that reason, I don't fully trust Nichicon HM/HN/HZ caps from 2005. If they read higher capacitance, then they may be overfilled.

I still use them, though - mostly for testing or repairing my own (non-critical) equipment.

[UserXP]

Re: HM HN, Dates for the bad boys?

Here is my contribution to the topic.

There are two 6.3V, 3300uF Nichicons HM series dated 0432 next to the heatsink on this older Gigabyte S478 board I have, and near VRMs there are three 16V, 1500uF Nichicons HM series also dated 0432. There are no signs of bulging and the board runs perfectly stable. The processor is a P4 at 3.0GHz and its temperature idles around 43 degrees (more when something is run).
So, these Nichicons were produced sometimes in the second half of the year 2004. They seem OK after so many years and use. Maybe these have a corrected formula.

On the other hand, I had to replace the 0522 Nichicons on another S478 board (we had a discussion here about that experience in my topic regarding that), so there it is. Datecode 05 failed, whereas datecode 04 still operates fine. I guess it did depend on a particular production line or something, right?

[momaka]

Re: HM HN, Dates for the bad boys?

^ Typical for problematic HM and HNs. The capacitance is actually not that high, but these capacitors develop high internal leakage and will fool an ESR meter.

[Behemot]

Re: HM HN, Dates for the bad boys?

Just found two HMs, 0227. They measure 4400 uF, seems that part of the problem may be somebody tried to push it too hard

[RJARRRPCGP]

Re: HM HN, Dates for the bad boys?

Whats the problem? The manufactured the board later yet loaded with old revision of BIOS.

The board is OK, no signs of bad caps. (Unless tests that were fine before suddenly fail.)

I just had it sitting. Because it won't let me OC.

"-VM"s especially that generation, prohibit OC'ing.

You must mod the board to OC a "-VM", especially the socket 462s.

It worked fine in 2007, the last time that it was on a lot.

"-X" boards usually allow a fair amount of OC'ing and Vcore changing.

[Behemot]

Re: HM HN, Dates for the bad boys?

Whats the problem? The manufactured the board later yet loaded with old revision of BIOS.

[RJARRRPCGP]

Re: HM HN, Dates for the bad boys?

Here's something interesting:

My Asus A7N266-VM has HMs coded 0310.

But the BIOS is August, 2002.

I hope this don't mean that Nichicon is using Seagate-like date codes, where
"10254" I think is actually in 2009! (And not 2010 like some people believe)

[Behemot]

Re: HM HN, Dates for the bad boys?

I believe the week 22 is NOT correct. H0452, 2200 uF/10 V from Intel D865 PERL, no source of excessive heat nearby (between SB and RAM) and it is very nastly bulged as all the bad HNs did/do.

Just for case removing also golden 820 uF/6,3 of H0447 in the CPU VRM. One strange thing, I have had the same board before, also with bad HN's, but there was more of them in the VRM. Is it only my impression or did Intel really use random ratio of Nichicon's HN and Chemi-Con's polymers??

[PCBONEZ]

Re: HM HN, Dates for the bad boys?

Thank you.

[oddbondboris]

Re: HM HN, Dates for the bad boys?

i know this is old and all but i've got 9 nichicon hm series 6.3v 1500uF caps in a 3com 2808 gigabit switch. all the caps are datecoded 0341 and all are bad
thing lasted 8 years in a no aircon environment on 24x7 somehow