Capacitor leakage

[horvendile]

After finally buying my new computer a couple of months ago (yay!) it's time to ready the old one for trickling down to my mother. Today I started cleaning it up physically (operation dust removal), whereupon I saw this:

How much should that worry me?

 

[horvendile]

Update.
Apparently I should worry about something, but maybe not primarily the capacitor - I believe it has looked at least a little like that for a while.
Here's the deal.
I booted with XP install disc. It appeared to hang, or at least take a long pause, at the very first "determining configuration" text screen (translated from Swedish).
I then tried booting into the old, installed XP. It worked, but slowly. XP says that my network cable isn't connected, which is clearly a lie (how many times shall I need to tell my computer not to lie about things that are so easily verified...?).
It also says that there is something wrong with my keyboard. Fair enough, it isn't working in XP, but in BIOS it works fine. Wtf...?
I beleive that it stops working at the bootup screen, right after the light-up of my three Lock keys, becuase then everything crawls a bit before booting resumes.

The only hardware changes I made were taking out my WLAN card and swapping the 9600 Pro for an 8500 LE. I expected graphics hiccups, but keyboard? And network?

This is such a weird problem that I don't really expect anyone to be able to help, but it's surely worth a shot!

 

[inefficient]

It's not that werid. This is a fairly famous problem that has been showing up in a lot of PC mobos.

There is even a web site devoted to the subject: http://badcaps.net/

 

[horvendile]

Hm... I was going to sell this system to my mother cheaply, but I'm beginning to feel that it should be very cheap...

 

[maaoouud]

Leaking caps is bad. Might kill the PSU and when the PSU goes anything can go. When my old board (also at mom+dad) died, it killed the PSU. Or the PSU died and killed the board in the process... you get the point :smile:

But your cap seems located next to the agp slot so it's probably there to stabilize the current to the graphics card. So a lowend card that doesn't crave much current might be ok. If the board dies my guess would be that it could kill the gpu aswell.

If you have a good soldering iron (needs to get rather hot) you could replace it yourself, a new capacitor is like 10-15SEK with the obligatory rip-me-off fee for buying just one. The hard part is getting all the solder out of the holes in the motherboard after you've freed the bad cap. I used a sharp and thin needle (actually used a few of them, they tend to bend under the pressure). Once you've got the holes good enough, so that you can put the new caps legs in (remember to take notes which way to place it.. just mark the motherboard with a softtipped pen at the side of the capacitors marking, the stripe) just put it in and flip the board over and solder away. And be careful not to use too much solder, it only takes a little to get the job done.

 

[horvendile]

But your cap seems located next to the agp slot so it's probably there to stabilize the current to the graphics card.

In fact, at a time I had problems with seemingly random reboots when the computer was booting, and just when it was going to switch from loading screen to Windows desktop. I suspected some sort of motherboard glitch, and this looks as a plausible culprit. On the other hand, the problem went away by itself.

I'm not much into soldering, and right now I'm wondering if this, with 512 Mb and without the service package, wouldn't be a better package for her. At 3000 SEK it's more than what I was going to charge her for my old system, but it's amazingly cheap for a new system.

 

[Sxotty]

Why don't you just get a new motherboard?

 

[horvendile]

Why don't you just get a new motherboard?

Good question, but I see that I haven't told you that when I say "the old one" I mean the old one...

It's a K7T Turbo from 2001. Socket A. The CPU is a T-bird 1200. Also, that's SDRAM we're talking.
It's so old that that I'm wondering whether the relatively large hassle of a motherboard swap would be worth it. I don't even know where to buy a socket A motherboard that would accept a T-bird!

I could buy a cheap motherboard, CPU and memory. But then I would also want a new PSU, and the price would be very near the Dell system and not really better.

 

[Simon F]

After finally buying my new computer a couple of months ago (yay!) it's time to ready the old one for trickling down to my mother. Today I started cleaning it up physically (operation dust removal), whereupon I saw this:......
How much should that worry me?

Hey, you should be thankful. AFAIU, until electrolitics were made with the "cross" indented on the top, they could explode rather than leak.

 

[Sxotty]

Good question, but I see that I haven't told you that when I say "the old one" I mean the old one...

It's a K7T Turbo from 2001. Socket A. The CPU is a T-bird 1200. Also, that's SDRAM we're talking.
It's so old that that I'm wondering whether the relatively large hassle of a motherboard swap would be worth it. I don't even know where to buy a socket A motherboard that would accept a T-bird!
.

I think it would not be nearly as difficult as you describe it. I have such a board sitting collecting dust, and am sure you could find one around your location as well. Even if that is not the case can't you put the processor into a newer board (though you would need memory still)

 

[_xxx_]

Why not just replace that capacitor? Five minutes of work.

 

[horvendile]

Why not just replace that capacitor? Five minutes of work.

Mainly because me with a soldering iron is the equivalent of a monkey with a typewriter - may produce Shakespeare, and then again, may not...

No seriously, thanks all for the advice. I'll sleep on it.

 

[SugarCoat]

The age of the motherboard is why you're having the detection problems such as keyboard and W/LAN under XP. If that was a motherboard from 2004-06 you wouldnt be having those issues. Thats not the capacitor fouling up. It was a great joy installing XP on those vintage motherboards, especially when you only had SATA drives! As far as i'm aware motherboards from Socket T and 939 and newer have zero issues. Everything before that required you to have drivers because for some reason windows XP vanilla drivers didnt recognize anything. Including the keyboard(usually USB) on some models. This was easily solved by having the driver disc or making one on a friends or different computer.


basically you have 3 options. Trash the computer, replace the capacitor, or replace the motherboard. There should be zero issue with finding an old Socket A motherboard if you have even a halfway competent dealer with a decent supplier. Finding something like soldering pen would actually be best for cap replacment since the tip is far sharper so you wont use way more then you need. That would problably cost you anywhere from 150-200 Kronor with the solder i would guess.

 

[Blazkowicz]

soldering is actually easy, I was taught it in school when I was 11 year old. (though soldering wires was annoying)

as for a motherboard swap : any socket A motherboard will accept your t-bird , so don't worry about that. you might try to find a cheap used one that still has sdram slots (such as a K7S5A or A7V133).

if you don't want to replace old unriable crap by some other old unreliable crap, get one with DDR slots (it will be much easier to find) and buy a cheap stick of 512MB. I managed to find a KT333 based mobo in new condition for only 15 euros (using it right now), on some french website which is a bit like ebay but without the auctions ( . less hassle!)
Socket A mobos are easy to find, more than Socket A CPUs it seems.

this would be better anyway if you only have say 256 or 192MB sdram. mom's PC doesn't need a better CPU at all but 512MB is nice.

 

[Frank]

Hey, you should be thankful. AFAIU, until electrolitics were made with the "cross" indented on the top, they could explode rather than leak.

Yes, exploding electrolytic capacitors is fun and messy. And dangerous, but that's part of the fun.

 

[Simon F]

Yes, exploding electrolytic capacitors is fun and messy. And dangerous, but that's part of the fun.

I remember sitting in a Uni' physics prac class and watching someone jump off their chair after they'd soldered in a large electro the wrong way and switched on the power...