Dead K9N Neo-f

[Joun]

Hello to everyone!
I am new to this forum and I have to say I am really impressed with the amount of information that exists here..
I have to say about myself that I am an electrical engineer and I deal with electronics for hobbie( or lately I think it is starting to be a side a side job..)
I have a pretty decent collection of tools and more than 25 years of experience as a hobby.
Lets get to the point now: I have a dead K9 neo-f motherboard..Before I found your forum I thoght it might be the BIOS's fault so I found I new one and replace it..
Of course nothing changed..
I now have to ask you if it is possible for capacitors to look OK and still be bad..I have desolder a few and measure them, the measurements were very strange..Since I have bought my capacitance tester mainly for impendace measurments I cant rely on it very much..
One last question: do you think I should invest on an ESR meter ?
Thank you..

[c_hegge]

Re: Dead K9N Neo-f

Those capacitors you de-soldered are Chemi-con KZG series. It is VERY common for them to fail without bulging. I'd try replacing them. The other caps are panasonic (the black/gold ones with the T-vent) and sanyo (the green ones). I can also see some el-cheapo Teapo caps there too (the blue ones with tristar vents) The KZGs and teapos have to go, the rest can stay.

[Joun]

Re: Dead K9N Neo-f

I will replace the ones you mentioned..
The problem is that where I live the only way is to order them so it's gonna take a while..
I'm thinking to buy a lot of cheap ones since I am not sure it's only the capacitors to blame..When I have the proper experience I'll start buying decent ones.I'm saying I don't want to waste good quality caps only to discover later that my motherboard still doesn't wakes up.
What about the ESR meter?Do you think it's necessery?
Thank you for your answer.

[tron]

Re: Dead K9N Neo-f

yes

first ESR meter, if you like
to fix SMPS and PCB
with clarity of the
internal resistance
of the cap

heres a nice one
http://www.radiodevices.info
but there are other ones

[Joun]

Re: Dead K9N Neo-f

Well since my Russian are a little rusty(don't know any at all,I'm Greek) I fell more confident ordering from an English speaking site.The truth is I have heard very nice comments for the ESR meter you have just linked me..
I also have that in mind(more pricey for sure): http://www.peakelec.co.uk/acatalog/jz_esr60.html

[PCBONEZ]

Re: Dead K9N Neo-f

heres a nice one
http://www.radiodevices.info
but there are other ones

Last I heard those were out of production due to parts shortages.

What about the ESR meter? Do you think it's necessery?

Depends on how often replacing caps comes up in your life.
.
You can't find bad low ESR caps without one but if replacing caps is not something you do frequently then an ESR meter may not be worth it.
[That is for you to decide....]
.
Many hobbyists get by with simply replacing all bloated and all 'suspect' caps.
'Suspect' = caps with known issues which you can find out about by asking or reading here.
'Suspect' = if they aren't bad yet they probably will be soon enough so you might as well replace them.
.
I probably repaired 30 or more boards before I even owned an ESR meter.
.
The times it helps:
- To find bad ones that aren't bloated.
- When you pull all the 'Suspect' caps off a board that won't work and they all check good - you'll know the board has some other problem like a bum 'good brand' cap or a blown MOSFET or chipset.
- When you want to replace as few caps as possible to test the board and see if it's worth recapping.
- To check new caps before installing because once in a great while a 'dud' does get through.

So, you don't HAVE to have one to do cap work but I highly recommend owning one if you FREQUENTLY do cap work.
.

[PCBONEZ]

Re: Dead K9N Neo-f

As to KZG. - Just replace them.
They go bad often enough it's not worth chancing they won't go bad later if they aren't already.
.

[Joun]

Re: Dead K9N Neo-f

Thank you for your answer..
And what do you think about my idea of getting a lot of cheap caps(like 10 for $1) and replace all of MB caps just to check if it is their to blame or to look somewhere else?
P.S Blown MOSFET or chipset? Should I check here for "usual suspects"(I mean in which part of MB they fail often) or somewhre else?
Sorry for the too many questions rookie on recapping here( I even learn such a word exists two days ago..)

[ipman]

Re: Dead K9N Neo-f

Joun, since you are quite close to Romania, there is somebody who makes a good ESR meter here.
The page is here: here
Shipping should not be too much, the meter costs around the equivalent of 40 euros, and since we are in EU you do not pay custom fees.

[Joun]

Re: Dead K9N Neo-f

Ipman thanks for the link,I wasn't aware of that..
I guess that you're using it yourself?

[tron]

Re: Dead K9N Neo-f

ESR-micro v3.1 model is available
and the sitemanager speaks English




Atlas ESR70 is even better,
because it protects itself from
occasional discharge

[Joun]

Re: Dead K9N Neo-f

Thanks for the info..
I'm waiting for an answer from the non-English speaking sites.

[goodpsusearch]

Re: Dead K9N Neo-f

Hi Joun! I am from Greece and Thessaloniki too!

Geia!

I will send you a pm in Greek trying to answer your questions.

Generally, I agree with what the previous users said.

Btw welcome here!

[Joun]

Re: Dead K9N Neo-f

Well it is true what they say, there are Greeks everyware..

[ipman]

Re: Dead K9N Neo-f

Yes, I am using it for almost half year. Nice tool, decent quality.
If you are interested, I can translate the specs.
In the mean time here's the construction details

Please note that I don't have any commercial interest in this, just trying to help.

[Joun]

Re: Dead K9N Neo-f

Thank you for your answer..
I have already translate the specs(thanks Chrome!) and I have send email to x-roast, waiting for his answer about shipping and way of payment..
You say it's worth it right?

[ipman]

Re: Dead K9N Neo-f

Works as it should for me, can't find any complaints about it.
I use Maha "true 9,6V" 8 cell rechargables instead of normal 9V PP3 block, which gives the meter way more than 10V at full charge. It will not enter stand-by because of that (was conceived this way) and the display is brighter.
Still, it has reversed diode protection inside and will not self-discharge capacitors as Peak ones do, but price is way lower.

[PCBONEZ]

Re: Dead K9N Neo-f

Thank you for your answer..
And what do you think about my idea of getting a lot of cheap caps(like 10 for $1) and replace all of MB caps just to check if it is their to blame or to look somewhere else?

I'd still use good caps.
Leave leads a little long until board is tested.
If board is trashed pull the caps for later.
If board works finish trimming the leads.

Blown MOSFET or chipset?

Look for cracks, pits, or shinny spots that indicate something melted inside.
On all the IC ships really.
Those are just most common to get blown by a cheap PSU or bad caps.
Most mobo MOSFETs are near the CPU and RAM sockets/slots.

Should I check here for "usual suspects"(I mean in which part of MB they fail often) or somewhre else?

You are looking for the brand and/or series caps that are problems.
Have to check them all really but definitely look at the mobo, in the PSU, and on the video card.

.

[Joun]

Re: Dead K9N Neo-f

Thank you for the tips Pcbonez..