Scratched mbo chip - No sound

[goran_10]

I scratched a mbo chip while installing a gpu. Now my back sound panel is not detecting speakers or any other device. Front panel is still working though, and giving normal sound output. The mbo is Asrock B250M. Is there a way to fix this?

Photos (it's the "nuvoTon" one):
http://i.imgur.com/xMw9zay.jpg
http://i.imgur.com/BnXH551.jpg

 

[nitinvaid20]

Lucky you its still working as sound chip is different from other circuits..
where there is nothing you can do now and i would recommend you to leave it like this if you dont want to damage anything else
you can buy soundcard tho..
which speaker you have 2.1? or 5.1?
if its 2.1 then you have to use the frontpanel now....

 

[BFG-9000]

That's not a scratch, you broke off a SMD ceramic cap. If you can't find it or its terminals are broken off just replace it with any ceramic cap that fits in that spot--the exact value is unlikely to matter much but the current open-circuit certainly does.

 

[goran_10]

There was no cap...see at Asrock's webpage, nothing's missing: http://www.asrock.com/MB/Intel/B250M-HDV/index.asp

A friend suggested I use some kind of electro-conductive varnish. Anyone had any experience with that?

 

[BFG-9000]

There's pretty clearly a brown cap there on Asrock's pictures. It's between the crab chip (the Realtek sound chip) and the electrolytic caps, between and slightly above that chip and the Nuvoton (Winbond) one.

 

[goran_10]

Sorry, I was too absorbed with the nuvoton chip to pay attention to anything else...do you mean this? http://imgur.com/a/xWUq8

 

[BFG-9000]

Yep, that's it. The raised shape of the pads suggests something had been there on your board too. Unfortunately these small ceramics have no markings on them for the value, but at least you can tell from the color it's not a resistor (which is what you could have used conductive paint instead of).

If you can't find it, measure the size and get one that fits off an old or broken piece of equipment to try.

 

[Phillip Corcoran]

Don't bother with all that shenanigans - - - just install a 7.1 sound card.

 

[goran_10]

Nah, can't find it. If I find a replacement how would I go about attaching it on?

 

[BFG-9000]

Hold it down with something metal and just touch the ends with a soldering iron, should just take a few seconds. You could probably even get away with electrically conductive glue such as "Wire Glue."

ALC887 is a fine 7.1 chip and it's such an easy fix, why waste an x1 slot?

 

[goran_10]

Will any of these work? I'm not exactly sure what I'm looking for.

Old Soltek mbo
http://imgur.com/a/OCZR6

Even older sound card (still works lol, but I only have one pic-e slot and it's occupied by my gpu)
http://imgur.com/a/47mbp

 

[BFG-9000]

Just find something rectangular that's tan or brown with no markings and the same size. If it's yellow it will have a polarity marking on it (with tantalum that's the opposite of the convention of stripe on negative) and could catch on fire if attached backwards. If you have to buy some try to get a range of values like 0.001mF = 1nF, 0.01mF = 10nF, and 0.1mF (ceramic caps have relatively high voltage ratings so you won't have to worry about that).

BTW that soundcard is 32-bit PCI, not PCIe. And Realtek bought Avance Logic which is why all their sound chips still start with ALC.

 

[goran_10]

Thanks for the extensive reply. I'll try it when I get hold of the soldering iron.