Only Stellar Wars and Flash used yellow flipper ROMs

The yellow (System 4) flipper ROMs were used on just two games, Stellar Wars and Flash. Upgraded System 3 and System 4 CPU boards can run System 6 (green) software, apart from Firepower.

Systems

• Williams System 4

Games

• Stellar Wars

Related tips

• Flash has yellow and green game ROM versions; match them to the flipper ROMs
• Flipper ROM colours: white, yellow, green and blue
• "Flipper ROMs" have nothing to do with the flippers
• Flipper ROM color codes by system
• Andre Boot test ROM flash codes
• Flipper ROMs at IC17 and IC20: replace the originals with new EPROMs
• Flipper ROM colour tells you the system generation
• Reading audit 00: game number, flipper ROM version and software revision

Source: Repairing Williams System 3 to System 7 Pinball 1977 to 1984, Part Two, Clay Harrell (pinrepair.com)