Is this a blown cap on my motherboard?

[mdesmarais]

Cap may or may not short when it goes. You should really be pro-active and change them out. Don't use old ones from an old board- they have already used a good portion of their lives. New ones are very cheap- no reason to cut corners. If you need to practice, find some other old board and play around- it is pretty easy.

 

[beelzerob]

It would be a great time to practice up at soldering too. I cheap soldering iron and a little solder is a cheap investment... and very handy to have and use. You can find all the helpful instructions you could ever want on-line.

Oh, it's not for lack of trying. It just never seems to work for me like it does in those oh-so-easy-looking pics and videos all over the web. It says to tin the tip of the iron with solder, and it shows a nice blob of solder on the tip afterward. I touch the solder to my iron, and it seems to practically vaporize, not nicely melt onto the tip. It says to hold the iron to the part until the solder starts to melt. 5 minutes later, I'm still waiting for the solder to melt. In the meantime, I notice that all of the plastic parts anywhere nearby are starting to deform.....

It's just never been good to me. I really do WISH I was good at it, as I agree it'd be a very handy talent to have.

Well, I do have plenty of spare motherboards around, so maybe I will indeed play around with removing some caps just for fun. Solder-based destruction should be manageable for my skill level.

 

[beelzerob]

Cap may or may not short when it goes. You should really be pro-active and change them out. Don't use old ones from an old board- they have already used a good portion of their lives. New ones are very cheap- no reason to cut corners. If you need to practice, find some other old board and play around- it is pretty easy.

You're right, and I will go ahead and get the caps. I took a pic of them to get all the info off of them, and I went to that bad caps website, but I couldn't find anything on the cap that indicated a manufacturer, and I couldn't find anything on badcaps.net that would let me look up the cap part via the motherboard model. So, how do I make sure I get the absolutely correct caps? Just from the farads and voltage and other stuff written on it?

 

[BLH]

Their main web site has preselected kits or individual caps.
Also a few tutorials on how to select caps and do the work.
http://www.badcaps.net/pages.php?vid=2

 

[beelzerob]

They don't have my motherboard maker listed (biostar), so I guess I just match based on voltage and farads then, right?

I have no problem buy from there, since it's a useful service they're providing it seems.

 

[BLH]

Maybe the physical size. Some motherboards used small circumference and taller capacitors. Some larger around and shorter in height.

 

[mdesmarais]

voltage/farads is ok- physical diameter too. Height if there may be interference (often not an issue in a PC) and don't forget the lead spacing!

From your description, it sounds like you have a dirty/burned/de-plated tip. try cleaning it- you should be able to make it shiny and clean. (wipe in on a wet sponge- carefully so you don't burn the sponge) If you can't get it clean, replace the tip.

 

[Dave X10]

..... It just never seems to work for me like it does in those oh-so-easy-looking pics and videos all over the web. It says to tin the tip of the iron with solder, and it shows a nice blob of solder on the tip afterward. I touch the solder to my iron, and it seems to practically vaporize, not nicely melt onto the tip. It says to hold the iron to the part until the solder starts to melt. 5 minutes later, I'm still waiting for the solder to melt. In the meantime, I notice that all of the plastic parts anywhere nearby are starting to deform.....

A clean soldering iron works much better than one encrusted with burnt carbon. A little sandpaper and a wire-brush could resolve you problems.

 

[mdesmarais]

A clean soldering iron works much better than one encrusted with burnt carbon. A little sandpaper and a wire-brush could resolve you problems.

Be careful- depending on the type of tip you have, this can destroy the plating. If it is already burned and pitted, that's a different thing. . .

 

[beelzerob]

Well, I've ordered the caps...they should arrive in the next day or so. And I'm beginning to get that scared feeling (again) that I'm in over my head on fixing this. I'm thinking this is beyond my meager skills, and too easy to end up destroying something. So....do one of you guys live close and wouldn't mind replacing 8 caps on a motherboard for some beer money??

 

[pete_c]

Take your time. I "lost" my HA box to bad caps while on vacation and just recently replaced MB with same model MB. Here's a guide sorts and a resource for you...I am replacing caps on bad MB just to have a duplicate HA box.

Badcaps dot net

 

[beelzerob]

Heh...badcaps.net is the place I bought the caps from. So I've been there a bit, and seen their "tutorials". I'm also well acquainted with how often they say "Be careful you don't __________, or you'll ruin your motherboard!!" My soldering skills are pre-kindergarten, so it just seems like this is the *perfect* chance to ruin an otherwise working motherboard.

I may go down and sacrifice an older board and see just how badly I do...but I fear that it's too easy to end up screwing up the little connections on the motherboard and not even knowing it.

 

[pete_c]

I tried a couple of months ago with one of three bad cap mini itx boards In have. I only replaced two caps on one of the boards and only got a BIOS beep so I believe there are more bad caps.

I initially used a vacuum type solder sucker and it worked some not well though. I then just heated the terminals one at a time pulling on one of the two leads. 2 of 4 leads left some solder. I then used solder sucker. It worked on one. I added more solder to the other lead but still had issues. I then used a small pin and it worked. Just a bit time consuming.

One of my 3 AP's went out also while I was on vacation. Checked it this morning and it has two bad caps. Its a Linksys WRT54G.

I asked my wife to pick some caps up at RS and she did. I'll do a pictorial of this fix and post it here....

In addition the Dlink POE adapter was partially melted. It was set to run at 12VDC. Its been fine for about 2 years. I did have a wierd power surge between Christmas and New Years.

I "cleaned" up some more after looking at the last picture. The ground on each cap was easy. The positive side was not.

It didn't work though and most likely something else is back. Maybe a surface mounted diode or the regulator....

BTW my wife is very patient with me. I did this on the kitchen table right before dinner (timeline). Years ago she wasn't patient with me when I started to rebuild a carburator in the house (SU type).

I'm really attached to the MB from the HA box and may send it in to BadCaps. The other three mini-itx boards most likely will attempt to fix. (these are from touch screens and firewalls)

 

[beelzerob]

Man...I wonder how many devices I've had that have mysteriously died and that's what it was.

I'll murder a motherboard tonight and see how I do.

 

[beelzerob]

Be careful- depending on the type of tip you have, this can destroy the plating. If it is already burned and pitted, that's a different thing. . .

Well, these tips aren't expensive, right? Should I just go get a new one from R Shack?

I tried out my complete lack of skills on a junk motherboard. I held the iron to the pin poking out the back of the motherboard, for like 1 minute...nothing happens. I pushed it into the little mound of solder at the base of the pin, and that managed to dissolve some solder. Trying to use the copper braid, I found the braid getting too hot to hold, but the solder underneat it still not melting. I finally quit and left the braid welded to the capacitor pin. Once again, it just seems like the iron doesn't heat anything. I can put solder directly on the iron, and it melts into it. But holding the iron to anything seems to go nowhere.

I can try the sandpaper and wire brush, as Ive got nothing to lose with this tip if it has to be replaced anyway.