Fixing Your Motherboard for $15

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Excellent article. You don't need a desoldering station or a computer controlled soldering station. There are little rubber desoldering bulbs and solder wick, and a cheap 25-30 watt soldering iron will work just fine. Technically you don't even need to remove the solder at all. Just heat one leg of the cap and rock the cap. repeat to each side alternately until the cap is free. Be sure not to overheat the board or you will remove the trace. Cut the leads on the Cap to a manageable length like 5 millimeters. Place the cap through the holes and solder in place and clip the excess lead. If the holes are clogged press the leads on the clogged holes and apply heat alternately to the holes the Cap will magically seat itself, then solder and clip. If you do remove the trace around the cap leg then get some thin solid wire and bridge the connection to a good part of the trace. It is so easy as to be ridicules. Or, if you are really lazy or are too scared, then you could always use the mobo for a Frisbee. Watch out though because they hook to the right.
 
I have a few cheap 300W PSUs that failed due to output filter capacitor failures - there is more to picking capacitors than nominal capacity.

Capacity aside, electrolytics used for power distribution and bulk decoupling have two important characteristics: impedance at their intended operating frequency (often 100kHz) and maximum RMS ripple (charge/discharge) current. What I have found in my cheap PSUs is that they use terribly under-spec'd filter caps: sub-1A RMS ratings on a 20A rails means the capacitors are very likely to be exposed to well over 10A of RMS ripple... no surprise these things routinely fail full-load testing even when fresh from the factory.

Under-rated RMS ripple current capacitors in PSUs is one of my pet peeves about PSUs: they rarely result in immediate catastrophic failures and will survive days, weeks or even months of moderate stress-testing before failing for good. When hardware sites review and endorse high-end PSUs, it is still no guarantee that these PSUs will endure the reviewed or rated loads throughout the warranty period.

After so many PSU failures, the first ones being with external HDD boxes a few years ago (these typically use the flyback topology which can produce very high capacitor ripple currents), I decided to order a bag of 100 Phillips 16V 2700FM capacitors (the lowest 100kHz impedance and highest RMS ripple current ratings I could find on a generally compatible footprint) and made it a standard practice to replace output filter caps at the first sign of PSU problems: spontaneous reboots - the degraded ESR/ESL renders the capacitors incapable of filtering voltage spikes from the PSU transformer stray inductance and trips the overvoltage crowbar protection increasingly often as the capacitors slowly and silently continues to degrade until total failure.

I have also found out that nearly all Linksys BEFSR and many WRT routers along with some D-Link models like the DI-524 suffer from relying too much on their electrolytics for decoupling: all those I owned started to behave erratically or failed after a year or so of service. All of them so far were restored to better-than-new operating condition after I soldered 1uF 0603 MLCC capacitors under at least one electrolytic near each IC for each voltage rail to supplement local decoupling. I started experimenting with this practice after my BEFSR81 became unusable even as a network switch over two years ago. Before I added capacitors in my D-Link router, the wireless link would never stay up for more than a few minutes/hours at a time but after adding the MLCCs, it now routinely stays up for 2-3 days straight and the average signal strength appears to be up 3-5dBm.

Right now, I'd say those 2700uF (~$0.70 each) and 1uF (~$0.08 each) caps along with my WESD51 soldering station are my best friends when I see hardware behaving mysteriously. I have not had motherboard capacitor failures yet but I am tempted to fit any open capacitor sites with 2700FM caps wherever the footprints may be compatible as a preventive measure and supplement electrolytics with MLCCs near sensitive areas to spare eletrolytics from decoupling most high-frequency noise.

Since I buy parts in bulk and have plenty of spares while I already own the supplies and equipment, fixing trivial faults in $30 hardware is still less expensive than replacing it as long as I have spare time and still have a use for whatever failed.
 
If you apply too much pressure to the metal pin, you might cause crazes in delicate circumjacent conducting paths.
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8O You guys seriously need to consider hiring an editor.

I'm all for bitching, but what is wrong with that statement? Punctuation?

Edit: In case you didn't understand let me put it into plain terms. If you press too hard you will damage/lift a trace.
 
I saw the title of the article and thought "probably fixing an old MSI motherboard" and sure enough, it was. I like how the author said it could be any board, but I think the title of the article ought to be "How to fix the caps on your malfunctioning MSI". And solder wick works fine - just be patient and keep your iron clean.
 
I have had some experience (good and bad) with desoldering modern pcbs and found that they are quite fragile. A couple of points are:
1. Be careful not to use too much heat for too long as the traces will disbond from the epoxy and leave you with a damaged circuit board. You can use very fine wire to repair it if you have too. Repeated heating to a high temp will cause damage.
2. I suggest practicing on an old board to get the technique down pat first. The right combination of soldering iron temp, tip tinning, timing and solder removal technique, when practiced will pay dividends in the end. Otherwise you just have to hope you are lucky.
3. Solder removal braid will cause the epoxy board to get hotter and increases your chance of delaminating the traces. It is the easy to use but has this rather unpleasnat disadvantage.
4. You would be advised to build a Jig to hold the board so you can work on it correctly instead of holding it with your elbow propped up with a book and the hand you are using to hold the solder iron.
5. In the absence of a professional soldersucker station a cheap one-shot solder sucker works good if you can hold the tip of the thing 90 deg to the board accurately positioned directly over the hole when you fire it. This way it will develop sufficient suction to remove all the solder in one shot. Squeeze bulbs are a last resort.

Hope this helps. Good to see a technical article like this - Kudos THG!
There are still a few spark chasers around sniffing rosin smoke and building/repairing stuff now and then.
 
Any recommendations on a decent/cheapy processor-controlled soldering/de-soldering station? I could actually use one of these with what I do.
 
OK

1. Never ever drill out the holes in your Motherboard. These are usually 6 layer boards and it will be easy to ruin it. If it is that stubborn, Retin the connection and try sucking it out again.

2. A hand held solder sucker will work fine, just don't use too much heat. If it isn't behaving, retin and suck again. Wick works to but it works better if you heat each side and remove the part before cleaning the pads with the wick

3. Electrolytic capacitors are responsible for around 90 percent of age failures on products. Japanese parts are much better quality.

4. Always keep your solder tips tinned. A bad tip will not work due to heat transfer. If solder flows into a ball and doesn't stick to the tip, your tip is bad.
 
A temperature contolled soldering iron and patience is all that is required to do the job. Not everyone has both of these but more common than a full desoldering station.
 
Excellent article. You don't need a desoldering station or a computer controlled soldering station. There are little rubber desoldering bulbs and solder wick, and a cheap 25-30 watt soldering iron will work just fine. Technically you don't even need to remove the solder at all. Just heat one leg of the cap and rock the cap. repeat to each side alternately until the cap is free. Be sure not to overheat the board or you will remove the trace. Cut the leads on the Cap to a manageable length like 5 millimeters. Place the cap through the holes and solder in place and clip the excess lead. If the holes are clogged press the leads on the clogged holes and apply heat alternately to the holes the Cap will magically seat itself, then solder and clip. If you do remove the trace around the cap leg then get some thin solid wire and bridge the connection to a good part of the trace. It is so easy as to be ridicules. Or, if you are really lazy or are too scared, then you could always use the mobo for a Frisbee. Watch out though because they hook to the right.
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Thank you!! You just saved me a lot of typing!!!

I have repaired dozens of mobos using this exact method. It works great.

I wouldn't bother though if the board doesn't post. I have never gotten a totally dead board alive again from replacing bad caps.

Boards that work, but freeze up the OS from bad caps though are perfect. A few minutes of work and you'll have no more freezing problems :)

I steal good caps from dead mobos. Not an option for everyone, but saves me from having to order them.
 
15$ for capacitors. All tools : 300$ ?
New mainboard : 150 $, i'll go with the new mainboard.
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Thank you. Not to mention the time, knowledge, etc. necessary to identify a problem capacitor and successfully correct it.

Reminds me of the machinist who spent an hour making a part he could buy at the local harware store for $0.14 plus tax.
 
I'm surprised nobody has mentioned http://www.badcaps.net/.

I came across this site when researching problems with my Abit BP6 several years back.

A decent site with some pics of ... well ... bad caps 😱 , instructions, replacement cap kits (for the most infamous bad motherboards), repair service, etc.

It looks like they are a bit pricey but they only sell high quality caps.
 
I wouldn't have bothered but I saw a lot of posts that appeared to be against the idea due to the high tech equipment etc., so I figured I would lay out the low tech approach.
@utaka95 I just checked my MSI NEO2 board and caps are still good. 8)
 
15$ for capacitors. All tools : 300$ ?
New mainboard : 150 $, i'll go with the new mainboard.
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Thank you. Not to mention the time, knowledge, etc. necessary to identify a problem capacitor and successfully correct it.

Reminds me of the machinist who spent an hour making a part he could buy at the local harware store for $0.14 plus tax.

Also not to mention that it doesn't take any time to identify a bulging/leaking capacitor all you do is look at it. And that capacitors are not that hard to replace and that it is a good skill to possess.
 
OK

1. Never ever drill out the holes in your Motherboard. These are usually 6 layer boards and it will be easy to ruin it. If it is that stubborn, Retin the connection and try sucking it out again.
Click to expand...

I disagree with that statement, a drill bit a tiny bit larger that the cap leads is usually smaller that the holes in the mobo. A little careful work with a twist drill can save mobo traces that may be ruined while you're trying to wick the solder out of the holes.
 
I wouldn't have bothered but I saw a lot of posts that appeared to be against the idea due to the high tech equipment etc., so I figured I would lay out the low tech approach.
@utaka95 I just checked my MSI NEO2 board and caps are still good. 8)
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The low tech approach should have been wha the article was about in the first place.

Hell I've even used the big crappy tire 200w soldering gun to do it :lol:
 
I wouldn't have bothered but I saw a lot of posts that appeared to be against the idea due to the high tech equipment etc., so I figured I would lay out the low tech approach.
@utaka95 I just checked my MSI NEO2 board and caps are still good. 8)
Click to expand...

The low tech approach should have been wha the article was about in the first place.

Hell I've even used the big crappy tire 200w soldering gun to do it :lol:

Yeah, they should have at least given the caveman approach as a low cost option in the article, but I guess that's why we're here. A 200w soldering gun is ballsy, you can melt the traces off in seconds.

Edit: Or should I say burn the traces off.
 
I disagree with that statement, a drill bit a tiny bit larger that the cap leads is usually smaller that the holes in the mobo. A little careful work with a twist drill can save mobo traces that may be ruined while you're trying to wick the solder out of the holes.
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On a 2 layer board is one thing. Causing an open in on through traces on the 4 unaccessable layers is fatal. I have never had to drill in 12 years of this kind of work.
 
So is it possible to bring back a mobo that doesn't post using this method? I currently have 4 of them in my closet, I don't need them but I could fix them and make computers to sell or something, I have a lot of spare parts.
 
Once i had a mb with a broken capacitors....who fell from a truck...
Anyway i cutted capacitor in the midle found a replacement one and soldered it on the legs of the old one... that was 2 years ago and the mb is still working...

Also i found out that Asus RMA frequently returns mb-s with notes "customer induced damadge" when capacitors or bios chips are faulty.
That means you have tu pay 15€ for a service...at least in europe.
 
15$ for capacitors. All tools : 300$ ?
New mainboard : 150 $, i'll go with the new mainboard.
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You only need $1.50 in tools. I use a generic solder iron from a local auto parts store's "cheap tools" bin

No solder sucker needed either, just leave the solder pool in place, and melt it to push the capacitor legs through.
 
This is a bit of a coincidence. Just last week, I repaired an old K7S5A with this exact problem. I didn't use any fancy tools, though. Just a Radio Shack soldering station and a bit of wick. I also ordered my caps from www.mouser.com, at $0.45 each with about $6.00 shipping, I replaced 7 caps for about $10.50 and have three spares. For the record, only one was actually bad, but after replacing it, I decided to go for all 7. It only took about an hour (25 minutes for the first one, 5 minutes for each cap after that).

I will definitely try this one again. I might even fix my Antec power supply which has a failing fan controller. Maybe it is related to a cap?
 
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