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Bulging Caps or just fat caps????

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First post, by Soap

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It was mentioned to me on here that the caps on my Geforce2 GTS Pro may be bulging and need changing, I said I would take some close ups and get them uploaded.

I think they are just fat caps but could be wrong, this GPU had been in the loft since about 2002 until recent, looks just how I remember it.

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Reply 2 of 33, by Soap

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Ah right I see, what kind of Caps would I need to order? Are the the little black things at the base a part of these caps?

Thanks

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Reply 3 of 33, by jmetal88

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Those are SMD electrolytics, and yes the black plastic bit will be included when you order new caps. Look at the labels to determine capacity and voltage, and measure the caps to see what size footprint you need to order (these can all be selected for in Digikey's or Mouser's search forms).

Reply 4 of 33, by pentiumspeed

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These little black bases is just that, base so they can sit upright without tipping over during soldering process and ease of manufacturing by consistently bending lead over mechanically.

By the way, they are bloated due to tops not flat and starting to cone. Replace them, and bonus is your board have through holes where each capacitors are, so you go ahead and buy radial electrolytic capacitors based on lead spacing instead of hard to solder SMD capacitors.

Cheers,

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Reply 5 of 33, by Soap

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pentiumspeed wrote on 2021-06-06, 21:26:

These little black bases is just that, base so they can sit upright without tipping over during soldering process and ease of manufacturing by consistently bending lead over mechanically.

By the way, they are bloated due to tops not flat and starting to cone. Replace them, and bonus is your board have through holes where each capacitors are, so you go ahead and buy radial electrolytic capacitors based on lead spacing instead of hard to solder SMD capacitors.

Cheers,

Thankyou both for the advice, i'll get onto the digikey now and borrow a soldering iron tomorrow.

Thanks again

Reply 6 of 33, by FAMICOMASTER

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They look fine to me. If they were bulging they would be out of the vent perforations at the top. The pressure required to bulge the main body would be more than is required to pop the cap on it's own.

Reply 7 of 33, by wiretap

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To remove those, one of these cheap pair of hot tweezers makes it super easy: https://www.amazon.com/dp/B01M2YHJAB/

They have terrible reviews, but work absolutely fine after they heat up for 2-3 mins. Just tin the tips, place the tweezers on the capacitor pads, and they lift right off with zero effort. Then you can use the normal soldering iron with copper wick and flux to clean the pads.

For the new caps, you tin one pad, hold the tip there for a second so it is molten, then slide the new capacitor into it and take the iron away. After it is cooled and solid, add solder/flux to the opposite pad and it is done.

Removal and pad cleanup should take 10-15 seconds, and install of the new capacitor takes about the same amount of time. Just don't have the iron as hot as the sun, because that's how pads can lift away from the board.

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Reply 8 of 33, by wiretap

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FAMICOMASTER wrote on 2021-06-06, 22:13:

They look fine to me. If they were bulging they would be out of the vent perforations at the top. The pressure required to bulge the main body would be more than is required to pop the cap on it's own.

They're definitely bulging, you can tell the way the light is reflecting off the top. Electrolytic capacitors have about a 10-15 year lifespan to be within their rated specifications anyhow, so they should be replaced. Beyond that, the electrolytic formula degrades and/or starts to dry up. They also get oxide layer degradation, which can only be partially fixed by reforming the capacitor out of circuit.

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Reply 9 of 33, by FAMICOMASTER

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I've seen televisions from the 1950s sit in the California desert for 40 years and come out working. Capacitors aren't as severe a failure as most people consider them to be. These aren't leaking and they don't appear to be bulging any more than they were when they were new.
If they were drying up they wouldn't be bulging.

Reply 10 of 33, by wiretap

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That's incorrect, since as they dry out, they get hotter during use and generate more hydrogen gas to begin bulging.

If you pulled electrolytic capacitors out from not being used for 40-50 years, they would certainly need to be reformed at a minimum, but more than likely need to be replaced. They would not perform anywhere near their rated specifications.. and they would fail in short order once heated up in circuit with hours of use.

I am not basing this off of "I saw this one time when.." - I'm basing it off failure analysis and EPRI topical reports since this is an area I work in daily in the nuclear industry with circuit boards mostly from the 70's, 80's and 90's.

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Reply 11 of 33, by cyclone3d

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FAMICOMASTER wrote on 2021-06-06, 23:04:

I've seen televisions from the 1950s sit in the California desert for 40 years and come out working. Capacitors aren't as severe a failure as most people consider them to be. These aren't leaking and they don't appear to be bulging any more than they were when they were new.
If they were drying up they wouldn't be bulging.

Tell that to the NOS Abit KT7A that had multiple caps that looked brand new and exploded the first time I powered up the board.

If the caps are bulging they are definitely bad.

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Reply 12 of 33, by wiretap

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Not to mention TV's from the 50's used very few can electrolytic capacitors since they were extremely expensive to produce. (over $80 each in today's dollars) They mostly used paper/wax electrolytic capacitors which would definitely dry and crack in a desert environment. They didn't even last long in the 50's when the TV's were brand new and stored/used indoors.. Hence the TV repairmen in high demand that would bring their capacitor kits to your door. (and vacuum tubes of course, which failed sometimes only after several hours of use depending on the manufacturing quality)

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Reply 13 of 33, by jmetal88

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wiretap wrote on 2021-06-07, 01:32:

Not to mention TV's from the 50's used very few can electrolytic capacitors since they were extremely expensive to produce. (over $80 each in today's dollars) They mostly used paper/wax electrolytic capacitors which would definitely dry and crack in a desert environment. They didn't even last long in the 50's when the TV's were brand new and stored/used indoors.. Hence the TV repairmen in high demand that would bring their capacitor kits to your door. (and vacuum tubes of course, which failed sometimes only after several hours of use depending on the manufacturing quality)

Yep, I've (electronically) restored a number of '50s TVs so I'm definitely familiar with these issues. 😀

Reply 14 of 33, by Jager

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I've seen similar capacitor on Hercules 3D Prophet II GTS 64MB. Replaced it with new, but it turned out that old one was perfectly fine, despite slightly dome-shaped top.
https://www.anandtech.com/show/571/2

Reply 15 of 33, by Miphee

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These caps are probably fine, here is another shot of a brand new GF2 Ti.

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Reply 16 of 33, by snufkin

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Just looked up the thread where the capacitors were questioned ( Re: Beige-Beast ). Are there any problems when using the card? I think I'd probably take the view that as long as nothing has leaked on to the PCB then if the card is working ok I'd just leave the caps alone. If you get graphical glitches when running video stress tests then consider changing them, and if anything has leaked then definitely take the caps off and clean the board.

Also, I wonder if the other motherboard and PCI graphics card you mention in the original post there could be got to work...

Reply 17 of 33, by Soap

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snufkin wrote on 2021-06-07, 08:31:

Just looked up the thread where the capacitors were questioned ( Re: Beige-Beast ). Are there any problems when using the card? I think I'd probably take the view that as long as nothing has leaked on to the PCB then if the card is working ok I'd just leave the caps alone. If you get graphical glitches when running video stress tests then consider changing them, and if anything has leaked then definitely take the caps off and clean the board.

Also, I wonder if the other motherboard and PCI graphics card you mention in the original post there could be got to work...

I have no issues after much stress testing and gaming, also have the memory over clocked and not a single glitch or crash.

There is no leaking, the reason I asked about fat caps is because on photos from reviewed units from 2001 they look exactly the same to me.

I'm far from a expert so seeked advice here as I wanted more opinions, I was taking the stance don't fix what's not broke as there is no issues in Windows or leaking.

Reply 18 of 33, by user33331

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I too think "bulging/exploding caps" are bought a little bit to extreme. ( John Haynes car books recommend changing transmission oil at least every 5 years. Have you done it ? )
I have never replaced capacitors or any circuit board parts apart from CMOS-battery and I have multiple fully working PCs from 1993, 1995, 1998 and a lot of consoles: NES, Gameboys, Gamecube, Wii, PSone, PS2,Xbox 1, Xbox 360 and such.

+I don't have the equipment to do any circuitry work. I have tried but have zero soldering skills.

Reply 19 of 33, by dionb

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user33331 wrote on 2021-06-07, 09:29:

I too think "bulging/exploding caps" are bought a little bit to extreme. ( John Haynes car books recommend changing transmission oil at least every 5 years. Have you done it ? )
I have never replaced capacitors or any circuit board parts apart from CMOS-battery and I have multiple fully working PCs from 1993, 1995, 1998 and a lot of consoles: NES, Gameboys, Gamecube, Wii, PSone, PS2,Xbox 1, Xbox 360 and such.

...nice list. Only devices from capacitor plague era on it are Japanese (those PSs), so didn't use crappy Taiwanese caps.

Play around with PC stuff from 1999-2003 and your experiences would be different. That's exactly the period this card is from, so the concern is more than justified.

As for exploding caps, 1993 is a bit too new for that but go a bit older and you can have lots of fun. I had a load of 1991 very early 486 boards NOS. Out of eight, three had tantalum caps that exploded on me when I powered them on. That's pretty typical for what you can expect.