The most prevalent and infuriating problems with these computers are the power supplies and the lasers for the CD rom drive.

Generation 1 Tower card capacitor list. C6 must be a snap-in large capacitor. Everything else is regular/average spacing

MICROFARAD VOLTAGE
C6 680UF 180V
C52 560UF 25V
C57 2200UF 16V
C60 220UF 50V
C61 330UF 16V
C70 22UF 25V
C74 22UF 25V
C75 22UF 25V
C54 220UF 25V
C55 220UF 25V
C58 820UF 10V



Generation 2, 3 and 4 power supply cards are just as bad due to the cards being vertical and acid leaking sideways. C6 is a snap in super capacitor.
C12 will make a whining noise when the computer is off with the power standby mode near the relay K1. This is how you know it's about to die. C57 will also leak extremely badly.

MICROFARAD VOLTAGE
C6 560UF 200V
C12 47UF 50V
C75 22UF 35V
C60 220UF 50V
C84 1UF 50V
C74 22UF 35V
C52 560UF 25V
C57 2200UF 10V
C58 1000UF 16V