3 video card caps blown. Can this be fixed?

[jackorocko]

First off I would like to know if fixing these 3 caps will help the video card? I am not sure why these caps blew.

I had a pair of wires coming from a motherboard fan that was run through the caps. I used the caps on the video card as a placeholder for the wires. Now I am wondering if the electromagnetic field created by those wires had any influence on the down fall of these caps???

When the video card first shown issues of going bad I was playing a game with my daughter on my lap. Instead of playing the game she was more interested in my keyboard. The video was fine until she pressed the windows key on the keyboard. As the screen went back to my desktop a bunch of artifacts popped up. I had to restart to fix the problem. After that the computer worked fine with minimal artifacts. It wasn't till about 8 hours later when I wasn't even on the computer that I heard the caps blow sitting in an adjacent room.

Now does this sound like it was my fault for using the caps as a placeholder for the wires or does it sound like this could have been an issue with the card and replacing the caps will do no good, as it will continue to just blow caps? I did have the card for close to 2 years before these caps blew.

Anyway here are the pics. Does it look like this card could be fixed and what are the pitfalls of trying to fix this card? Also, what vallue are these caps? 2 x 1500uF/6.3v and 1 x 1000uF/6.3v electrolytic caps??? What type should i be putting back, any specific manufactures???

 

[NickS]

I knew that windows button was bad news.

Joking aside sure you can replace them and its probably not your fault they died. I have replaced caps in dead samsung monitors and DVD players thus far and the equipment has always come back to life.

You are looking at surface mount caps so be careful not to pull the pads up when you de-solder them.

Other than that you already have what you need to find replacements. I don't subscribe to one manufacturer as the best. I would try to keep the ESR low and if you want longevity you can pick parts with long lifetime ratings. Really it will be a balance of cost/performance. I usually try to stay in the middle of that road.

Good luck
-Nick-

 

[shrtrnd]

Another possibility to consider, is the wires from the fan. Check the fan wires carefully, to make sure no insulation rub-through, exposing the wire itself to the cap can package. Kinks in the wire, or previous exposure to some heat on the board, could have simply caused an electrical short. My guess is pretty much like NickS, to save space and money, manufacturers often put a lot of little caps in the place of one big one. One cap blowing, would easily result in the loss of three in the same circuit.
Hope that's your only problem, good luck.

 

[Mitchekj]

To add, pick some 105c rated caps if possible. Every 10 degrees C you keep them below their rated temp, you double the lifetime rating.

E.g. Cap A is rated 2000 hours @ 105c. The cap's case measures 65c. Now you can expect ~32,000 hours.

Cap B is rated 2000 hours @ 85c. The cap's case measures 65c. ~8,000 hours lifetime.

 

[jackorocko]

http://www.badcaps.net/forum/showthread.php?t=8413

Well what do you know, I have the badcap issue Cheap ass xfx.

anyway, lets get to the point. in this thread they link me to some caps for sale on that badcaps.net site. I see they have a particular brand they sell. MCZ and MBZ. What is the difference? I checked out ebay and can buy extras for close to the same price as badcaps.net I would prefer buying from ebay but they have both mbz and mcz types. So what should I be looking at as the difference in those two series caps? Why choose one over the other?

I know a low ESR value is good. What else is important?

NickS, I don't think these are surface mounts. They have pins on the back side of the board. So that shouldn't make a difference as far as what you was talking about?

edit: thank you mitch and Nick. I will look into those differences in the series caps I am looking into purchasing

 

[Mitchekj]

Aaaahh, hahaha. Those are SMD caps, they've just folded the leads straight and removed the plastic bases, then used them as thru-hole. That's funny. Wonder if they had a height issue.

Edit: And heed the advice in that forum's thread... replace all those cheap-o FZ series caps while you're at it.

 

[jackorocko]

I'll purchase the extra caps once I get the card back to working order. I might be making a huge mistake, but I don't see those caps blowing within a week. If they do then I have wasted 10 dollars and will still have some extra capacitors left over.

btw. How does one de-solder a SMD cap? just heat the lead on the top and push the cap to the opposite side. Most of the FZ caps are through-hole, but 2 of them are SMD with the plastic guard.

 

[NickS]

Lets see here.
(1) I would buy the caps from a part retailer like digikey or mouser or newark not ebay. That gives you a lot more flexibility in the parts you order.

(2) They are definitely sitting on surface mount pads but that explains why the pads look un-tinned. Thus is a sighn that 1 you need to pay attention to the hight of your replacement caps for clearance concerns at Mitchekj brought up. But you are also in luck for re-work because you can now pick from surface mount or leaded caps.

(3) Removal. Do you have a soldering iron or heat pencil and flux? I am sure there are many methods for removal and everyone likes their own because it works for them.
For surface mount I like to add a little more solder to the pads then flux them up and hit it with hot air until the solder reflows on both sides then lift carefully with tweezers.

For through hole I try to snip one of the legs so that I can remove one lead at a time. If that is not possible then I heat one lead until I can back it out a bit then the other and repeat until it is either out or you have enough room to snip leads.

You will find what works for you but remember there is a balance. To much prolonged heat may damage other parts but working to fast will tear up pads and traces.

 

[(*steve*)]

Looks like you'll be working very close to some BGA components.

Be *very* careful you don't disturb them. Both because you won't know if you've done it, and because you won't be able to fix it either.

If they are mounted through-hole, your task will be far easier.

Once you get them removed, clean up the board too, it looks like there's some "stuff" on the board (looks like at least one of them died with a puff of magic smoke)

 

[NickS]

Good call Steve. You should try to do a rough clean of the board before you start. Electrolyte can be many things(including sulfuric acid), none of which are good for inhaling when you start heating things up.

 

[jackorocko]

Actually I looked t digi and newark. They do not carry those series or for that matter even rubycon caps at digi or mouser. I would prefer to stick to the badcaps.net website and use what others have already used with success.

I had a thought to look up some old power supplies and see if they had some of the caps i needed, but I was unsure if they would be up to quality for the application. I know buying new caps and high quality will benefit me more then trying to scavenge and repair the board multiple times.

 

[Mitchekj]

Anything from digikey will be high quality. As far as their stock of caps go, anyhow.