They're usually 10uF/16V, but these values are not critical (just don't go any lower with the voltage). Pay attention to polarity when installing them, especially those on the negative rails.

quicknick wrote on 2022-06-21, 22:03:

They're usually 10uF/16V, but these values are not critical (just don't go any lower with the voltage). Pay attention to polarity when installing them, especially those on the negative rails.

Good stuff, cheers 😀

Hello, how you doin'?
Dude, I'm blown.
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Yes, 16V 10µF is correct.
Tantalums exploding is a rite of passage I guess 😀

I suggest going with 25V rated caps instead. Usually the ones that pop are 16V rated caps located on the +/-12V lines, and given that tantalums tend to take voltage spikes quite badly I think that is one of the main reasons for the explosions. With 25V there is more of a buffer for that failure mode.

Agree with all the above and yes my Asus ISA-386C does have 10uF Tantalums. Actually was thinking of changing to regular Electrolytics when I change them out. Those bloat and leak but never explode 😀

I guess you could make the argument that an exploding tantalum is a good indication that you have a problem, as opposed to a sneaky slow leak 😁 But either way it's probably a decade or so before you have to worry. Still on the fence about which way I'll go.

Tantalums do have their pros. They have very low inductivity, very low ESR, don´t dry out and are perfect to filter high frequencies. When tantalum
was still cheap everybody preferred them. Then the tantalum price-shock happened and everybody turned to regular electrolytics.

A few aspects have to be considered:
1. Tantalums are more likely to fail when they operate near their nominal voltage. To be on the safe side here just use 25V or 35V tantalums for the 12V rails and 16V for the 5V rails.
2. Tantalums don´t like "hard" switching. At startup older (AT) PSUs used to raise the output voltages more slowly. Today´s ATX PSUs start very quickly and output voltages rise to the nominal values in no time. This can stress tantalums. Decades ago tantalums had to be protected against that by adding a resistor, today they have become much more tolerant and stable.
A typical effect is that tantalums still run perfectly in an old system with the original PSU. When the PSU is replaced by a modern one several tantalums die when the system is powered up the first time.

On many older mainboards you see regular electrolytics but in some critical positions (like clock-gen) there are still tantalums.

Job done. I went with electrolytics (2x 16V and 2x 25V) and these were the wrong approach for one reason: They don't quite fit in that little space! So they're kind of sticking out at different heights and angles, looking like the Big Book of British Smiles. I will not be providing a photo.

But I'm very happy to have my board back in service. Thanks for the advice everyone 👍