MSI K8 Neo4

[ChaosLegionnaire]

Re: MSI K8 Neo4

Today I bought my new PSU (EVGA SupaNova G2 750W) for my new build

good! shows that u know your stuff now. that is the best psu to get currently. its based on the superflower leadex platform and has 100% all japcaps. its ultra low ripple will ensure that your mobo and hard drive will last a very long time!

C11 decided to go out in a nice blaze of glory. This is the cap that had a chip of the brown covering missing that I mentioned in my first post but again I'm pretty sure it had been like that for years. It's right next to the atx12 4 pin plug.

I'll be gutted if that little smd cap is all that was originally wrong, I probably could have replaced it but getting the value of it I would have not had the faintest idea. Could that little cap have stopped the whole vrm from working full stop?

lol errr i already warned u in my previous post about that chipped/cracked smd mlcc. doesnt mean that its been like that for years, it will continue to remain that way forever. that is why u NEVER ignore bad caps!

u are quite lucky it didnt make a huge crater in your mobo. if it melts a trace and/or makes a crater in the board, its a goner. just ask momaka, he has personally witnessed cracked/chipped smd mlccs making large craters on boards with the copper completely exposed!

i think credit can be given for the new evga g2 psu for having *fairly* fast and quick short circuit detection. it tripped when the smd mlcc shorted out, saving a huge crater from being made in the motherboard! thats a good psu at work there, saving someone's butt!

hopefully, its not too badly charred around there and its still fine. u *must* now remove the smd mlcc from the board before applying power again. its shorted out and powering on the mobo is just pointless now and it will just keep shorting and frying the board in that area further, resulting in further damage.

seeing as how the smd mlcc is near the atx 12v connector, its probably a redundant power line noise filtering cap. there is usually an overkill number of those scattered on pcbs so its actually okay to remove it first, *then* power on without adding back a replacement just to see if the mobo is still alive. its only an issue if u intend to overclock where absolute stability and cleanliness of the power supplied to the board is a must.

momaka, that "little bit" was at least 10 years. I got the thing free, and in the perhaps 6 years I've had it it hasn't faltered once, until maybe now if it was indeed responsible for killing the motherboard. I'm not saying it isn't crap (now that I know a bit more about PSU's), it is ,but that crap lasted a lot longer than I would have thought.

where we are coming from is that we dont want other new members reading this and thinking it is okay to get away with using a junk psu. that is simply misleading to other new members who are also learning this stuff.

the real reason why that mobo lasted so long with that junk psu was most probably because of the branded japcaps on the mobo. the japcaps on the mobo held their own against a junk psu and gave u 6 years of service until something else crapped out. thats the real reason to give credit for the system lasting 6 years. we are strongly against giving credit to "a junk psu lasting for 6 years". that is simply not true here...

what im curious is, what hard drive did u use with that system? im surprised a hard drive can last 6 years without failing on that junk crapful of ac ripple psu.

bianchi77, I found the CPU box today, it's an Athlon 64 FX (FX-55) from 2004 so the vcore would be 1.50V, not that that matters now.

now, be careful about that. dont *assume* anything. there are apparently two versions of the fx-55 according to this cpu list from wikipedia. one is the clawhammer version, the other is the san diego version.

the only way to identify them apart is to look at the last 6 characters of the model number. check the model number sticker on the cpu box. if it ends with "DEI5AS", its the clawhammer 1.5v version; if its "DAA5BN", its the san diego 1.35v-1.4v version. dont wanna be getting the voltage wrong and possibly ending up with fried hardware or ending up redfaced and wondering why the computer wont post...

[ml2]

Re: MSI K8 Neo4

good! shows that u know your stuff now.

I wouldn't go that far but thank you for the comment.

I found a schematic for the 7125 board. It's not the same revision number as mine but I did find C11 in it, which is 10U. I've attached that part of the schematic.

I removed that now blown smd cap. No holes in the mobo but part of one pad on the board for it is gone by the looks of things. An axial lead cap could probably be put back in it's place with some very good soldering. Not sure about another smd.

Now for what I hope is the good news, after removing that smd cap I plugged the EVGA PSU back in. Upon shorting the ps-on pin to ground the whole thing sprang back to life. I plugged the video card and monitor in and saw the POST on the screen. Went into the BIOS and checked everything out and redid all the settings. In fact I'm using the mobo right now to type this out! The board doesn't seem to miss not having -5V.

I measured just a fraction over 1.5V on the VRM Fets. The BIOS auto sets the vcore voltage and it's giving 1.5V; I don't overclock.

So, if someone much smarter than me can look at the schematic, would leaving C11 off be of any real detriment or should I try and locate another one very soon? I'm still going to build a new system but having this one working again buys me some much needed time to do so.

what im curious is, what hard drive did u use with that system? im surprised a hard drive can last 6 years without failing on that junk crapful of ac ripple psu.

The HDD's are both Hitachi Deskstars, 500GB. Both still going strong. The only issue I ever had was when the cheap sata cables I was sold went bad. Replaced them and no problems ever since.

ChaosLegionnaire, I must also say to you, I am sorry, you did try to tell me about that smd cap and I didn't try doing away with it when you said. Can you forgive me I should have asked if it was safe to do away with it in the first instance.

I have no argument with what momaka was saying, crap is crap and I am now more aware of what is crap and what isn't. Both crap PSU's are now in the "salvage the fans and toss the rest" bin. I was just trying to say that that crap PSU was still going after 10 years and by the looks of things may be responsible for one smd cap going bad in all that time. One of these days if I get an oscilloscope I might put it on and see what it's doing, see how bad it actually was.

[ChaosLegionnaire]

Re: MSI K8 Neo4

I measured just a fraction over 1.5V on the VRM Fets. The BIOS auto sets the vcore voltage and it's giving 1.5V; I don't overclock.

ok. so we can safely assume your cpu should be the clawhammer version of the fx-55.

So, if someone much smarter than me can look at the schematic, would leaving C11 off be of any real detriment or should I try and locate another one very soon? I'm still going to build a new system but having this one working again buys me some much needed time to do so.

it looks like c11 is in parallel with the other electrolytic caps and before the CHOK1 inductor coil. its being used as an emi and noise filtering cap. its fine to continue running without it since u said u dont overclock. u just cant have the tv or radio near the mobo now because the lack of the emi filtering cap c11 *may* cause radio/tv signal interference. thats about it.

if it was near the cpu tho, that might be a different story as it may be for clock signal decoupling. there is usually no redundancy for those. if one goes, the cpu's clock signal may have too much jitter, the cpu cant even boot. tho in some cases, if it *still* manages to boot, u can salvage the situation by quickly rushing into bios setup-> cpu config and reduce the multiplier or downclock the cpu by around 50%, then quickly save the bios settings before the system can lock up. that should stabilise the clock signal since its running at a lower frequency. the system should be stable even at load again.

The HDD's are both Hitachi Deskstars, 500GB. Both still going strong. The only issue I ever had was when the cheap sata cables I was sold went bad. Replaced them and no problems ever since.

nice... good drives! recent info from backblaze has shown that hitachi makes the most reliable hard drives.

ChaosLegionnaire, I must also say to you, I am sorry, you did try to tell me about that smd cap and I didn't try doing away with it when you said. Can you forgive me I should have asked if it was safe to do away with it in the first instance.

i guess i can forgive u since the board was still saved after all. if it had fried the board and made a crater, i would be quite upset as i luv retro computer stuff. i'd hate one of the nicest boards for the athlon 64 to get trashed like that and end up in the landfill! that would then be unnecessarily generating e-waste through carelessness!

[bianchi77]

Re: MSI K8 Neo4

Gents, I must apologise, I am such a tool this week I was reading mV and not even realising it.

So to recap with correct values, with the ATX12 4 pin plug connected to the board nothing worked; no life from the CPU and the PSU would not turn on, (ps-on pin would go down to about 14 mV when shorted to GND, not go up to 14V as I had said).

When measuring the FET's as instructed by ChaosLeginonnaire I would get a reading of 2.8mV, not 2.8V so the PSU still wouldn't turn on.

Now we get the interesting part for today. Today I bought my new PSU (EVGA SupaNova G2 750W) for my new build and hooked it up to the K8 board to take the measurements again. This is what happened. C11 decided to go out in a nice blaze of glory. This is the cap that had a chip of the brown covering missing that I mentioned in my first post but again I'm pretty sure it had been like that for years. It's right next to the atx12 4 pin plug.

I'll be gutted if that little smd cap is all that was originally wrong, I probably could have replaced it but getting the value of it I would have not had the faintest idea. Could that little cap have stopped the whole vrm from working full stop?



momaka, that "little bit" was at least 10 years. I got the thing free, and in the perhaps 6 years I've had it it hasn't faltered once, until maybe now if it was indeed responsible for killing the motherboard. I'm not saying it isn't crap (now that I know a bit more about PSU's), it is ,but that crap lasted a lot longer than I would have thought.

bianchi77, I found the CPU box today, it's an Athlon 64 FX (FX-55) from 2004 so the vcore would be 1.50V, not that that matters now.

You got a blown / broken ceramic cap there...no idea, what the value is...but
it can be 100nF to 1000nF...

[bianchi77]

Re: MSI K8 Neo4

any luck ?

[momaka]

Re: MSI K8 Neo4

Now we get the interesting part for today. Today I bought my new PSU (EVGA SupaNova G2 750W) for my new build and hooked it up to the K8 board to take the measurements again. This is what happened. C11 decided to go out in a nice blaze of glory. This is the cap that had a chip of the brown covering missing that I mentioned in my first post but again I'm pretty sure it had been like that for years. It's right next to the atx12 4 pin plug.

I'll be gutted if that little smd cap is all that was originally wrong, I probably could have replaced it but getting the value of it I would have not had the faintest idea. Could that little cap have stopped the whole vrm from working full stop?

Yup, that small ceramic cap was the problem indeed. They like to go short-circuit when they fail, which is why your power supply was tripping. That said, your new 750 Watt EVGA SuperNova is much more powerful than the old junky PSU you had, so that's why it was able to blow ceramic cap before tripping and falling into short-circuit protection mode.

As far as the value of that ceramic cap: if you want to put in a replacement, I'd guesstimate that cap is anywhere between 1.0 uF to 4.7 uF, based on the physical size. Probably rated for 25V or more. But it's not necessary.

You can often take those ceramic caps from other broken hardware and reuse them. I do that all the time.

i think credit can be given for the new evga g2 psu for having *fairly* fast and quick short circuit detection. it tripped when the smd mlcc shorted out, saving a huge crater from being made in the motherboard!

Actually, that ceramic cap was already shorted when the EVGA SuperNova PSU was plugged in. If anything, the higher output power capability of the SuperNova PSU is what allowed it to blow that shorted ceramic cap away, due to slightly slower short-circuit protection. The old wimpy PSU probably couldn't provide even 1/3 of that power, hence why that shorted ceramic cap didn't blow up with it.

But I agree, credit still goes to the EVGA SuperNova PSU for finding and "fixing" that shorted ceramic cap for the O/P.

seeing as how the smd mlcc is near the atx 12v connector, its probably a redundant power line noise filtering cap.

It's not redundant, but it's not critical if missing either.
Like you said, it stops some of the EMI/RFI from the CPU VRM switching to go back in the PSU, but so do the other caps too. So with that cap gone, you will just have a bit more EMI/RFI than before. I doubt the lack of this cap will cause any problems, even with the CPU overclocked.

the real reason why that mobo lasted so long with that junk psu was most probably because of the branded japcaps on the mobo. the japcaps on the mobo held their own against a junk psu and gave u 6 years of service until something else crapped out. thats the real reason to give credit for the system lasting 6 years. we are strongly against giving credit to "a junk psu lasting for 6 years". that is simply not true here...

I agree 100%.

momaka, that "little bit" was at least 10 years. I got the thing free, and in the perhaps 6 years I've had it it hasn't faltered once, until maybe now if it was indeed responsible for killing the motherboard. I'm not saying it isn't crap (now that I know a bit more about PSU's), it is ,but that crap lasted a lot longer than I would have thought.

I also have a lot of crap PSUs that are equally old and still "working". The problem with these cheap power supplies is that they are far too simple, which is why they almost never completely stop "working". But just because they appear to work doesn't mean that they are. It's the other components in the system that are taking the toll from being powered from a "dirty source". And the worst part is, these low quality PSUs rarely have any protections and/or filtering to stop surges and voltage spike on the power line, which can easily damage hardware if it ever happens. I think you got lucky that nothing happened to your PC for so long. Most people I know who used such a low quality PSU (myself included) have gotten our lessons and know better now.

In my case, I never had anything damaged. But I did loose quite a bit of hair trying to figure out why an old Pentium II PC I had (back in the days) would crash when playing certain games, but not others. All of my hardware was really low power stuff, so it never even crossed my mind that the PSU could be the problem. I always thought it was the S3 Savage 4 video card and its crappy drivers. Then I changed the PSU for another slightly less crappy PSU. And what do you know? - that PC suddenly started behaving itself in all games and under any load.

[ml2]

Re: MSI K8 Neo4

any luck ?

The motherboard is powering along ok without the SMD cap in place. I can't say if it's as good as it ever was when it had it but it's stable right now. I am being careful of how much stress I put on the system though, and what I turn on and off that on the same power circuit as the system.

From the circuit I posted back in message 22, The cap is apparently 10UF. Because there are no real obstructions in that area I'm probably going to try and find a leaded ceramic 10U cap to replace it (if it's worth doing that); with part of the pad gone soldering another SMD on will be quite difficult but I should be able to bend leads 90 degrees and solder them into the pads.

momaka, I'm sure I've learn't my lesson. I can't say I'll ever know whats good and whats crap just by looking at it, but look at it closely is something I will do from now on, and if I don't know, I'll post about it.

Thanks all for your help.

[momaka]

Re: MSI K8 Neo4

The motherboard is powering along ok without the SMD cap in place. I can't say if it's as good as it ever was when it had it but it's stable right now. I am being careful of how much stress I put on the system though, and what I turn on and off that on the same power circuit as the system.

Don't worry about stressing the PC too much, it will be fine.

From the circuit I posted back in message 22, The cap is apparently 10UF.

Ah yes, I forgot you found and posted a schematic.

If you haven't done any SMD/SMT soldering, then don't bother replacing that cap, especially with anything else other than a ceramic cap again. Either way, it will be a pain if you don't have good flux. And with the pad nearly gone on one side, it will be even more annoying to solder to.

momaka, I'm sure I've learn't my lesson. I can't say I'll ever know whats good and whats crap just by looking at it, but look at it closely is something I will do from now on, and if I don't know, I'll post about it.

It's no that hard to spot the really bad PSUs.
- If it's light, it's probably NOT good.
- If it has thin wires (typically 20 AWG), it's NOT good.
- If the label has no (or very few generic) certifications (like UL with a valid number, FCC, TUV, CSA with a valid number, CE, etc.), then it's NOT good.
- If you can't see any input filtering through the vents (i.e. you see jumpers), then it's NOT good.

We even have a whole thread dedicated to low quality, blown, and gutless PSUs:
https://www.badcaps.net/forum/showth...?t=8490&page=3

[bianchi77]

Re: MSI K8 Neo4

try replacing those caps and see what happen ?