A few months ago I tried to fix an old monitor that had gone, literally, on the blink. As it was an intermittent fault, it seemed to have worked, but it didn't last. I tried one more trick, replacing the large cylindrical capacitor in the centre of the beige circuit board below, but that didn't help. I think the larger ones can break more subtly, rather than bulging or popping like the little ones.
So it's been taken to the ~~tip~~ household recycling centre.
I could've carried on replacing components at little cost, but you do have to admit defeat sometime!