Sonnett's own app "Metronome" shows when the Cache is enabled/disabled. It's enabled and presumably OK when Sonnett's extension is running, but I can only get all the way through the boot process about 10% of the time when that damn extension is enabled (I'm running 7.6.1). I'll try CPU director.

Unfortunately, I'm experiencing random freezeups and weird PMU issues (no boot, clicks, etc, though these might just be a dead PRAM battery) since I put in the G3.

Any advice on that?