VOGONS


First post, by sdz

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The card worked fine without the daughterboard installed, or with a know good daughterboard. At a first look, it didn't look that bad, there were a few scratches but no broken traces.

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However, the right TMU, TMU0, showed signs of corrosion on about 25% of the pins.

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The legs/pads would not take new solder, regardless of the amount of flux used, so I removed it to see what the actual damage is.

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While the pads are still there, more than 90% of the affected ones don't have a connection to the traces anymore.

I proceeded to scrape off the soldermask and the corrosion until I could see bare copper. And it was worse than I expected.

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Last edited by sdz on 2024-02-07, 17:07. Edited 1 time in total.

Reply 1 of 4, by sdz

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Next I checked if the vias were still connected to the corresponding TMU1 and FBI pins, as well as GND and VCC. Most of them were salvageable.

The pads were really corroded even underneath, and when touched by the soldering iron, they would instantly lift. So, wire and liquid soldermask it is. Solder a couple, use soldermask, UV cure, and repeat.

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After all pads were fixed, and the soldermask cure, I scraped off the soldermask where the new TMU would be soldered:

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Last edited by sdz on 2024-09-21, 11:13. Edited 1 time in total.

Reply 2 of 4, by sdz

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Soldering the new TMU was a bit of a pain, but doable:

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There was also a broken 10R resistor array, and after fixing that the card runs nicely in SLI.

Reply 3 of 4, by Ozzuneoj

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Amazing work! That would have been quite an undertaking, but to get an X-24 working it was definitely worth the time. 😀

Now for some blitting from the back buffer.

Reply 4 of 4, by sdz

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Thanks! It wasn't actually that bad, quite a straightforward fix. And yes, fixing these cards is worth the time 😀