MSI K8N Neo4/SLI (MS-7100) died, bad caps?

[nurio]

My setup
AMD Athlon 64 X2 4400+
MSI K8N Neo4/SLI (MS7100)
4GB OCZ
ATI X800

The problem is that the motherboard would not boot and the power supply wouldn't kick in: No fans start, the PSU power led doesn't turn on… I suspect the the problem is related to the power-on circuit not sending start cmd (closing circuit) to the PSU.

I tested all components (including the PSU and the case power switch) and they all work fine with a different mobo.

Before the mobo completely died it started having power-on issues a few weeks ago:
- It won't wake up from sleep.
- In order to turn on the computer I had to unplug it from the wall and plug it again.

I have inspected the mobo, but couldn't see any suspicious caps: no swelling, no leakage…

Questions
1. Any idea if these symptoms could indicate on bad caps (or even transistors)? Or the mobo is a goner.
2. If caps, then where should I start?

Thanks for your help,
Nurio

[nurio]

Re: MSI K8N Neo4/SLI (MS-7100) died, bad caps?

Last night I inspected the mobo again and then I noticed that one of the MOFSET (APM7313 ) has a brownish discoloration on the top and some brown substance around its legs.

I was wondering if this could be an indication for a bad MOFSET? How can I test it? Could one of the caps near it (KZE 470micF 10v 105degC) have killed it and need to be replaced?

I attached a couple of pics, but unfortunately I don't have my camera with me, so I took them using my cell phone and the quality is bad.

[momaka]

Re: MSI K8N Neo4/SLI (MS-7100) died, bad caps?

What brand (and what model) PSU are you using? How many amps on each rail?

[Toasty]

Re: MSI K8N Neo4/SLI (MS-7100) died, bad caps?

I'd be more interested in the caps and MOSFETs around the CPU than I would those down by BIOS. Pics of those with branding and series would be much more useful.

Also - swap the PSU with a working unit and see what happens.

See this thread for info too:
https://www.badcaps.net/forum/showthread.php?p=67583

Toast

[severach]

Re: MSI K8N Neo4/SLI (MS-7100) died, bad caps?

Testing the power supply is not the same as opening it and inspecting the caps. Another board may be much more tolerant of bad power. Ignore the warranty sticker. Open it up.

The cap could only have killed it if the cap was bad and that can be tested. Nothing brown comes from a burned chip so unless it's rosin which would only be on the solder then it would be a leaking cap next door. Caps with a poor seal will leak out the bottom onto the board without bulging the top or pushing the bung out. Caps can also dry out with little or no bulging or leakage. Clearer pictures would help. An ESR meter will tell all.

What I do with a board I want to keep if the ESR meter can't find the problem in circuit is take out and test the caps one by one working from the most suspect to the least suspect switching among the different suspect styles hoping to get an early lead on the bad ones. If I can find bad ones in the first few then I evaluate and repair. If I get all the way to the last cap and can't find a single bad one then it must have been something else.

[nurio]

Re: MSI K8N Neo4/SLI (MS-7100) died, bad caps?

First, I want to thank you all for replying!

@momaka
The power supply I used with the system was an Antec Phantom 500 (dual rail I believe), which seems to be in a good shape; I have been testing it in a different system and it's working. I have also tested the mobo with a new working PSU (that I bought, thinking that this is a PSU problem), so the problem is definitely with the mobo.


@Toast
The reason I was looking at this part of the board was, because I noticed the brownish color surrounding the MOFSET and also because I assumed (probably wrongly) that it might be part of the ACPI circuit as it is close to the front panel power switch pins and the BIOS. I did some more research on ACPI circuits and found this article , which makes me think that the ACPI circuit is actually above the CPU.

I have read this thread before, but I want to point out some differences between the two mobos:
- My board is an SLI (MSI K8N Neo-4 Platinum SLI, MS-7100), which has a slightly different layout.
- The biggest difference that I can tell is in the caps, in the same place where Ginguskhan had Chemicon KZG and KZJ, I have Panasonic (Matsushita).
- No visual signs of bloating or leakage.

Would you recommend replacing the Panasonic caps by the cpu, based on the resemblance between the boards?


@severach
I will open up the PSU as well and check it internally.

The capacitor by the MOFSET seems to be intact; I don't see any leakage signs and the brown substance might be some flux or something that wasn't cleaned out before leaving the assembly line.

I don't have an ESM meter and this is my first attempt to repair a mobo. Is there any place you would recommend buying from (preferably cheap and reliable)? or brands?


I attached a pic with the caps marked in colors by manufacture, hopefully this would make more scene to someone.

The caps on the board are:

KZE - Green
1. 10v 470uF 105°C
2. 25v 100uF 105°C

G-Luxon - Red
6.3v 100uF 105°C

Panasonic (Matsushita)? Has a logo with the letter M inside of a square - Purple
1. 6.3v 1000uF 105°C FJZ
2. 10V 1000uF 105°C FL
3. 10v 1000uF 105°C FJ
4. 6.3v 1800uF 105°C FL
5. 16v 1800uF 105°C
6. 6.3v 3300uF 105°C CFJ

Nichicon - Turquoise
16v 470uF 105°C

KMG - Orange
1. 10v 470uF 105°C
2. 16v 470uF 105°C

Unknown – Too small, has some vertical round equal signs from top to bottom - Yellow
16v 47uF 105°C

[Toasty]

Re: MSI K8N Neo4/SLI (MS-7100) died, bad caps?

KZE & KZG are United/Nippon Chemi-con. Will have a small shield symbol, no manuf. name.

Nothing glaringly bad about those you have onboard.

Swap the PSU with a know good one and see.

Toast

[Toasty]

Re: MSI K8N Neo4/SLI (MS-7100) died, bad caps?

Nevermind. I didn't read your reply to momaka.