Can a motherboard virgin (me!) replace my bad caps?

[Kappa]

I have a faulty MS-6340 mainboard in a five/six-year-old noname PC bought from Staples (UK) in around 2000. The PC started showing weird symptoms only a couple of years after I bought it, but at the time I had other stuff to deal with so I just stuck it in a cupboard and used another PC. Now I've dug the Staples/6340 out again, cleaned dust off the m/b (bristle brush/Hoover) and got it going. But the erratic working is soon evident (BSODs, fatal exception errors, freeze-ups, sudden reboots). I got it working for long enough to wipe the hard disk and reinstall 98SE from scratch. I also used System File Checker/Scandisk/Scanreg, so I reckon the software is okay. This is a basic machine. No NIC. No cards other than the graphics card. I've disabled the onboard sound chip. Often I switch the PC on, the green power LED comes on, the CPU and power supply fans come on, but there is no POST, zilch. Then I power down the machine, pull the power cord, tweak* one or two of the large caps, and ten-to-one this lets the machine reboot again - till the next time the failure occurs.

I suspect the capacitors are faulty. See my pics at http://www.visualbasic.fsnet.co.uk/Capacitors-1.jpg and .../Capacitors-2.jpg. The tall ones marked (A) in the first jpg don't look too healthy, do they? (The ones at (B) look okay.) The big question: Can I replace these myself? I have soldered circuits before and can use a solder pump! But I am not an electronics wiz (motor fitter by trade originally). Is this a difficult job? Since I could probably buy a replacement m/b for £50, it may not be worth the hassle. I have read elsewhere that m/b's have several layers, so maybe soldering in new caps is not something that beginners can do. Any comments are welcome!

* gently rock cap 1 - 2 mm from side to side

[kc8adu]

Re: Can a motherboard virgin (me!) replace my bad caps?

i suggest you read a bit here and learn about the tools and parts needed.
you definatly have a case of badcaps.a replacement board will likely fail the same way.
i would practice on scrap boards and get some experiance first.

[gonzo0815]

Re: Can a motherboard virgin (me!) replace my bad caps?

Well i would say it isn`t that hard. Actually some basic soldering skills are required too. Most important take a good soldering iron, i suggest some about 50 to 80w, preferably tempcontroled and long life chisel tip. And there are some tip cleaner aorund (no, not the usuall wet sponge, "tipy" small dose with some cleansing flux and powdered thin). I noticed recently, that they are very very good for soldering at high temp. The holes are small and you need a very clean tip to conduct the necesarry heat. if you don`t want to spend a fortune for an iron, i suggest either the Weller W60P with an 450°c tip or one of those like in the attached pic for ultra small budget. i have the cheap one, if the tip is cleaned, you can recapp with it. But the tip is not a chisel and the heat is not that mutch, that you can do a busines with it. But for about 7€ there is nothing better i think. And obviousely, the board isn`t worth that mutch.

[Kappa]

Re: Can a motherboard virgin (me!) replace my bad caps?

"a replacement board will likely fail the same way."

I don't understand. Why should a replacement board fail?

[Kappa]

Re: Can a motherboard virgin (me!) replace my bad caps?

Well i would say it isn`t that hard. Actually some basic soldering skills are required too.

I have not used lead-free solder yet. Is this old m/b likely to use lead-free?

Are these caps easy to get hold of? (As in: purchase)

[gonzo0815]

Re: Can a motherboard virgin (me!) replace my bad caps?

No, leadfree is only after mid 2006 used. May be some months early but not before the end of 2005. At least on motherboards and other IT stuff.
The caps are usually not easy to get, but depends on where you are located you can order them from the owner of this site if you are located in the USA or from other sources. Lock at the recapping section, there are some distributor listed.

The replacement board will have the same ugly badcaps as your actuall. So nothing won on the long time.

[arneson]

Re: Can a motherboard virgin (me!) replace my bad caps?

Lots of guys come here posting exactly what you did.
They decide to try it cause it's fun and challenging.
They post back that they got the caps.
They post back that they put them all in and it's working.
Then they're hooked, able to fix anything, a new found skill.
Absolutely go for it.

[Topcat]

Re: Can a motherboard virgin (me!) replace my bad caps?

I don't understand. Why should a replacement board fail?

Because it'll be loaded with the same shoddy caps that killed the one you're battling with now.

[Kappa]

Re: Can a motherboard virgin (me!) replace my bad caps?

The caps are usually not easy to get....

There are four large caps and two smaller ones (all about 30mm high, 12mm dia).

The large ones are all 4700uF 6.3V
The smalls are 3900uF 10V

I've found the large ones at Farnell UK (Panasonic EEUFM0J472L).
But for the small ones Farnell only do 3900 6.3V, not 10V

Is it imperative that these exactly match the ones I'm replacing?

[Kappa]

Re: Can a motherboard virgin (me!) replace my bad caps?

Because it'll be loaded with the same shoddy caps that killed the one you're battling with now.

Sorry, I meant that if I chose to fit a replacement board, this would be a brand new recent make/brand, using e.g. an AMD Sempron. There's no way I'd just buy the *same* board!

[Topcat]

Re: Can a motherboard virgin (me!) replace my bad caps?

Sorry, I meant that if I chose to fit a replacement board, this would be a brand new recent make/brand, using e.g. an AMD Sempron. There's no way I'd just buy the *same* board!

In that case, you would likely be ok, as long as you buy a good quality board from a manufacturer that uses good caps.

[dood]

Re: Can a motherboard virgin (me!) replace my bad caps?

Kappa- everyone has to start somewhere. You have the advantage that you are used to soldering other components. Even folks like Topcat had their first motherboard they ever recapped . It all has to start somewheres.

[Topcat]

Re: Can a motherboard virgin (me!) replace my bad caps?

Kappa- everyone has to start somewhere. You have the advantage that you are used to soldering other components. Even folks like Topcat had their first motherboard they ever recapped . It all has to start somewheres.

Off the record, I destroyed the first board I ever recapped, I was refining the stainless pick technique and poked the tube through the board. It obviously never worked again. That had to have been 10 years ago, it was an old socket 7 board. The second board I recapped was a 100% success. Practice on a scrap board first, refine technique, and give it a shot. Seeing that the board doesn't work anyway, what do you really have to lose?!

Good Luck whichever path you choose.

[Kappa]

Re: Can a motherboard virgin (me!) replace my bad caps?

....poked the tube...Seeing that the board doesn't work anyway, what do you really have to lose?!

This tube thing: I read about it in your How To notes. A close-up pic would be nice! The tube must surely be mighty small to sit in the mobo, which is very thin. This seems to me like the biggest potential cause of failure.

I agree that I have nothing to lose! The mobo's broken, so I can't make it any worse. However, it looks like sourcing the right caps in the UK is going to be a problem. If I do get the caps and the repair is successful, it will be a pretty cheap repair! These caps are dirt cheap (around 70p/$1.30 each).

[elbrute]

Re: Can a motherboard virgin (me!) replace my bad caps?

"I've found the large ones at Farnell UK (Panasonic EEUFM0J472L).
But for the small ones Farnell only do 3900 6.3V, not 10V

Is it imperative that these exactly match the ones I'm replacing?"

Kappa, replacing 10v with 6.3v should be OK.

elbrute'

[tazwegion]

Re: Can a motherboard virgin (me!) replace my bad caps?

The 10v components have been used for their low 'ESR' values, 6.3v of same capacitance will be fine

[yanz]

Re: Can a motherboard virgin (me!) replace my bad caps?

Lots of guys come here posting exactly what you did.
They decide to try it cause it's fun and challenging.
They post back that they got the caps.
They post back that they put them all in and it's working.
Then they're hooked, able to fix anything, a new found skill.
Absolutely go for it.

you are sharp

[grand_amatic]

Re: Can a motherboard virgin (me!) replace my bad caps?

I am myself a noob at this. I have the infamous A7N8X Deluxe board and I have 2 Bad Caps and recieving the dreaded blue screen of death. I have alittle background in soldering from my radio shack days...believe me nothing to be proud of just a bunch of old people who broke the IR led on their tv remote. But I have contacted chris and he is sending me 4 caps. I have printed out the how to guide and found a few other people that posted how they did it. Any thing i should do first....any info would be great...thanks Keith Golden

[willawake]

Re: Can a motherboard virgin (me!) replace my bad caps?

good luck. practice first