Replacing Motherboard Capacitors?

[cmort666]

And since no one else has mentioned it yet, you might want to try to find out what is frying them before you start replacing them, unless you buy them by the dozen. The soldering section in the above tutorial might give you some clues to look for.

I gather from badcaps that this is a fairly common problem because some manufacturers, ECS in particular, are using garbage caps these days. It kind of reminds me of my Norinco M1911: absolutely first rate barrel, frame and slide, and utter **** hammer, trigger, sear, and leaf spring.

 

[cmort666]

The larger electrolytic capacitors on motherboards and in the power supplies are prone to failure over time, even if you have good quality components to start with.

The current consensus seems to be that ECS uses substandard caps, with ASUS starting to follow their lead. When I started using ECS they were pretty good quality.

These capacitors usually use thru-hole leads, which are reasonably easy to remove from the board without damaging the board, but just be sure to use a lower-wattage iron rather than a solder gun, which would apply way too much heat.

I've got a soldering pencil that I last used to make a wired shutter release for my DSLR. I have done desoldering, it's just been a long time.

These capacitors typically fail either shorted, which is often easy to spot, or "open", in which case finding the bad one can be difficult without removing it from the board and checking it with a capacitance meter. They'll often also fail in groups, so you may want to change out the whole set. (Remember that these usually are "polarized", with a plus and minus side like a battery. DON'T put one in backward! )

From what I've seen, the general consensus is to at least replace all the similar ones around it as well.

I plan to take multiple photographs of the board, top and bottom, before doing anything.

 

[cmort666]

Look for capacitors that have become domed on the top when they should be flat.

I checked last night, and found one on the identical board which failed last year. I had to check twice, but eventually found a very obviously bad one off to one side of the board. I'm going to replace it and those around it.

I'm going to check the one which just failed, today.

If things work out, I'll have not only my desktop back, but a better personal Linux server than the one I'm using now (ECS K7SVA).

 

[cmort666]

My advise is to toss the MB and buy a new one on the auction site for $50. Buy heatsink paste (artic cool, i believe) and reuse the memory and processor. You are going to spend hours looking for the failed component and then search for a replacement.

The problem is that EVERY one of the working boards on ebay is in China, and listed as refurbished. Besides, those boards are discontinued. I'm stuck with whatever is sent to me... which may just blow eventually anyway.

I'll risk $8-$12 bucks for a reversing ring or an A/D converter board, but I'm leary of risking $50-$60. I think that if I replace EVERY cap on the board it won't cost me $20.

 

[cmort666]

I checked the board of the machine that failed this week, but didn't see any bulged caps. I haven't tried looking for leaks at the bottoms yet. The one that died last year looks like a good candidate for repair. In the meantime, my mother will give me the money I need to replace the MB, CPU, and memory.

I'm getting by on my mother's old laptop with Ubuntu on it, but I need to have a working Win 7 machine. I needed to send out a couple of resumes this week and had to recover one from an already sent email.

I have nothing to lose by trying to replace the caps on the one that had the bad cap. I've got a working Linux installation on the drive that came out of it when I used it to replace the Win 7 machine. I'm going to take another look at the one that died this week to see if it's really capacitors or something else. I'm betting on the former.

 

[Jellybean]

I gather from badcaps that this is a fairly common problem because some manufacturers, ECS in particular, are using garbage caps these days. It kind of reminds me of my Norinco M1911: absolutely first rate barrel, frame and slide, and utter **** hammer, trigger, sear, and leaf spring.

I'm not trying to shift the thread, so I hope no one goes postal...

I am a little more familiar with the Norincos. I built a few 1911s, before everyone and their brothers got into the act, and found a slightly used Norinco in a gun shop. It had gone through two owners before the store took it in on trade, they knew it jammed but couldn't figure out why. I didn't really care, I only wanted the frame and maybe a couple of other parts if I needed them. As I was tinkering with it, I found the problem, the slide stop was out of spec. and was rubbing against the magazine.

 

[cmort666]

I got the board with no apparent bad caps working again.

I had previously taken the memory out and reseated it, without fixing the problem.

I took it into the office of a friend with whom I've built systems previously, and started over from scratch. We pulled the board and closely scrutinized it for damage without finding any.

We pulled the CPU and reseated it, without fixing the problem.

Finally, we pulled the memory and reseated it, without fixing the problem. I suggested that my friend pull the modules one at a time. He pulled one and it still wouldn't turn on. Then he swapped them and put them both in and it started.

I bought some more thermal paste on the way home. I re-pasted the CPU and reconnected everything and now it works.

In the meantime, my mother sent me some money for a new CPU, MB, and memory. I'm going to retire this machine as my primary work machine and transition it to a client machine for my Server 2008 and Server 2012 MCITP studies.

By the time I'm done, I'll be able to study for the RHCE, 2008 MCITP and 2012 MCITP (or whatever they call it now).

I still plan to replace the caps on the other A780GM-A board, as I can use it as a better personal Linux server than the current server with the K7SVA. That's what my current A780GM-A was before the other one had a bad cap and had to be replaced.

 

[TucsonMTB]

I got the board with no apparent bad caps working again. . . .

Excellent. Congratulations!

Thanks for sharing the good news.