Common iMac G3 Slot-Loader issues:

Other issues that are common across all computers from this time include failing hard drives, dead PRAM batteries, and dust/dirt causing issues.

This Mac has a built in CRT! Computers with built in CRTs are all prone to issues like dimness, burn-in, and other high voltage related problems.

WARNING: This model of Macintosh uses the 3.6v half-AA lithium batteries for PRAM backup that are known to leak, and even explode in computers as recent at 1998. Slot-loading iMacs first came out in 1999! Remove this battery as soon as possible if you have this model! For more information on leaking PRAM batteries, go here.