Is the monitor the problem?
"I can hear the sound. I think the game is playing, but can't see the picture." Most likely the 1980's monitor has failed. Instead of struggling to fix an old 30 plus year old CRT monitor, how about let's replace it with a brand new LCD flat screen display. CRT monitors(AKA picture tubes) are rapidly becoming extinct. The EPA doesn't want that in the land fills. Production of them is limited because of the chemicals used to produce them is harmful to the environment. It's often cheaper to replace than repair. We can't Warrantee a monitor that old. With a new flat screen from Cliff's Home Amusement Services, Inc. you get a crystal-clear picture with 1 year manufactur's warranty. The new flat screen runs much cooler and so you don't have all that fine black dust that gets drawn into the cabinet and onto the screen surface and everywhere inside the cabinet. A new monitor is definitely the way to go if you have a 19 inch screen. For purists and larger size monitors we can rebuild the chassis and restore your monitor's functionality but there's no warrany.
All new screens have a one year manufacturer's warranty, 30 days labor.