I've had iMac G5s "snap out" of this mode (albeit sometimes only temporarily) when I reset the PMU/PRAM.
Also, sometimes the capacitors aren't specifically "bulging" at the waist, so to speak, but sometimes in the early stages the tops of the capacitors get a little pointy, if that makes any sense, when they are starting to bulge. The tops should be completely flat, so if they are starting to open up at the top, like a flower just beginning to bloom, that is also a sign of the flaw.