My monitor won't lite up

Check for an image using a flashlight. If it's stable, then it's likely a bad backlight tube or capacitors. However, it’s generally a capacitor fault that can be salvaged with a complete recap of the power supply board.

If the capacitors look okay or a recap didn’t work, the problem usually lies with the power supply inverter or the CCFL tube in the panel. Sometimes this is fixed with a power supply, but it rarely fixes the problem when a recap doesn’t work. Mine lasted ~1 year with a recap and ended up with a failed backlight the second time (check for a black end on the tube). It’s generally difficult to replace this and you usually ruin the panel in the process if you never done it before.

The problem in your case is it's likely like mine where a new power supply won’t fix the problem because of a bad panel as the failure of the backlight is more unique - when the tube fails, you usually lose it within seconds while a capacitor failure is more gradual and doesn’t happen without warning. Since the panel is old, expensive and out of production, you’re better off recycling this and replacing it if the caps pass. Beyond attempting a capacitor replacement, it isn’t worth repairing the monitor.