Have recapped several motherboards, all but one with success. And some video cards plus a PSU or two thrown in for 'flavor'.
Even if the capacitor shows no external signs, such as domed top or lifting off the board, internally it may be bad. Only the low ESR type capacitors should be used.. they have less internal
Equivalent Series Resistance, and thus are favored for sensitive circuitry. The rating as to Micro Farads must be identical, as well as the voltage rating. Never use a lower voltage capacitor, but a higher voltage capacitor is sometimes acceptable. The preferred temperature rating for computer use is 105° C. A lower temperature rating could mean a premature failure. Certain brands are well known to have been "born bad", as noted in the thread about "Bad, Bad Capacitors" here on the Forum.
Sometimes, a capacitor may go for years with no problem, then suddenly go DOA. Heat is a major enemy of capacitors.
Some capacitors are intended to filter out the ripple or AC factor of DC power supplies.. others are intended to keep separate the DC voltages between circuits, yet pass the AC pulses.
An AC capacitor is merely two DC capacitors, connected in reverse serial fashion ( negative lead to negative lead, the positive leads brought out for connection).
The modern "dry" capacitor is now used all across the industries. No more "wet" capacitors, as years ago. Thankfully, they have gone out of favor. Not good to smell an acidic odor coming from a device as the capacitor's electrolyte boils off!!!
Sorry for the ramble.
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