Hi,
Suddenly one of my dear Macs has decided to give up. Heres the story.
I ordered what seemed to be a good condition 22" Apple Cinema Display with DVI. It arrived, so I took a most appropriate matching machine - A 450MHz PowerMac G4 AGP. Even the color of the Apple logos perfectly matched (not technically relevant, I know). Later I found out that the odd 62W power adapter was somewhat fried, so I took to a local repair shop to see what they could do. Fast forward to now - this machine hasen't been booted since that moment, which is about 4 months. Today I decided to play some games on it, fetched an also perfectly matching 15" DVI Apple Studio Display, plugged it in and pressed the power button. To my surprise the monitor was not showing anyting. The machine did chime and booted successfully to Jaguar. I could tell that because I could change the volume and hear the corresponding sound. First though was that the dud Cinema Display has fried the video card, I hade a spare RAGE card, so I swapped it, booted but the same behaviour persisted. With that in mind I started looking up the issue on the web and came to the inevitable suggestions - resetting PRAM, PMU. So I tried both to no success, and now it's even worse! First the machine stopped making the chime, and after some more more twiddling around - replacing the motherboard battery, unplugging everything and leaving it alone for 10 minutes, now it's making a very strange ABRUPT chime! I've never heard a machine do anything like that! Attaching a video demo: https://youtu.be/S0GD1K-cJw0