It's possible that the Power Analog Video (P.A.V.) board might need replacing. This is a common problem with all the iMac G3 lines, "Molar" Power Mac G3 All-In-One and eMac models. You can find used good replacements on eBay and Craigslist. A lot more cheaper than they were in 2004; then about $300-$400, now about $25-$30 each.

73s de Phreakout. :rambo: