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It's here! Wanna see dead polymer? Yeah?

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    It's here! Wanna see dead polymer? Yeah?

    Well, you won't actually see it - as long as I don't have anything which could be taken as real camera. But let's start from beginning.

    There was a great hype last year with baking video cards (yeah, I mean in oven). Basicly somebody tried to bake an old VGA to see whether there are just some broken soldering points either under/in GPU or somewhere else. Guess what, it worked than so this spread all over the world. Now some people are still triying this even if the problem is usually somewhere else (like for Radeon HDs 4xx0 - usually VRM or something dies here). But hey, you could try, it won't do any more harm.

    The problem is, there is hard solder used on all newer cards so it often dies again after time because the solder didn't melt at all, it just softened. That's the reason I'll try my HD 3870 to be just heated in oven an than I'll continue with hot air pistol (550 °C) - I am certain it could be because of broken solder points (after my Accelero lost pressure when my PC fell from bed), I was increasing it for so long that it won't boot at the end).

    Also most of the people bake the card with capacitors on - and this is one of them. So the great deal is visibly leaked Nichicon (this guy said that won't matter) and X-CON ULR's. Result is a few of them are visibly bloated, capacitance is 30-40 % lower. As for ESR, well, I used meter with scale as folows:

    0,1
    0,3
    1
    3
    10
    etc.

    It showed me 3 for all caps so I gues all of them are considered as bad now (e.g. ULR 470 uF/16 V has ESR as low as 0,011 Ω in datasheet).

    Anyay, they did not die under service, just did not handle 200 °C first and than quarter of hour at 250 °C.
    Less jewellery, more gold into electrotech industry! Half of the computer problems is caused by bad contacts

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    #2
    Re: It's here! Wanna see dead polymer? Yeah?

    Moral of the story, if you're baking video cards, always remove the capacitors, even if polymer?
    "Tantalum for the brave, Solid Aluminium for the wise, Wet Electrolytic for the adventurous"
    -David VanHorn

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      #3
      Re: It's here! Wanna see dead polymer? Yeah?

      If you go 550c, you will cause the solder to come out the sides and you will have to reball it.
      "We have offered them (the Arabs) a sensible way for so many years. But no, they wanted to fight. Fine! We gave them technology, the latest, the kind even Vietnam didn't have. They had double superiority in tanks and aircraft, triple in artillery, and in air defense and anti-tank weapons they had absolute supremacy. And what? Once again they were beaten. Once again they scrammed [sic]. Once again they screamed for us to come save them. Sadat woke me up in the middle of the night twice over the phone, 'Save me!' He demanded to send Soviet troops, and immediately! No! We are not going to fight for them."

      -Leonid Brezhnev (On the Yom Kippur War)

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        #4
        Re: It's here! Wanna see dead polymer? Yeah?

        I've seen a video of BGA reballing on Youtube. Doesn't look extremely hard but I guess it would be expensive.

        Flux, solder balls, stencil, knife-tip for your iron, and then some way to reflow the chip again afterwards.
        "Tantalum for the brave, Solid Aluminium for the wise, Wet Electrolytic for the adventurous"
        -David VanHorn

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          #5
          Re: It's here! Wanna see dead polymer? Yeah?

          toasty Sanyo OS-CON's from a Sapphire HD3850 512MB DDR3
          bought this card as defective (random pixel-salad) on ebay.. mainly for the two-slot cooler exhausting hot air out of the case for my own HD3850, which came with the rather noisy single slot cooler.

          after i got it and removed the cooler, it became apparent that the previous idiot... pardon.. owner threw this thing into the oven to "fix" it..

          every single cap on there had popped, and the few Sanyo OS-CON's were half-molten at the bottom and had a slight bulge at the top..

          makes me wonder for how long he left it in there... and at what temp.. !?





          hard to see, but it's bulging a bit at the top. you can clearly see it and feel it in real life.


          next to a good one (right)

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            #6
            Re: It's here! Wanna see dead polymer? Yeah?

            Originally posted by Agent24 View Post
            Moral of the story, if you're baking video cards, always remove the capacitors, even if polymer?
            Exactly. I doubt some known "good" brands coudl even explode, you never know.

            mockingbird: why is it? I'll do it only for a few 30 secs or so.

            Anyway, I'll solder only some liquid elytes on the back side whether it will boot or not after baking. I don't have the nerves to solder it in the holes because of all the copper on PCB and hard solder used just to discover card is dead and I have to remove good caps again
            Less jewellery, more gold into electrotech industry! Half of the computer problems is caused by bad contacts

            Exclusive caps, meters and more!
            Hardware Insights - power supply reviews and more!

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