[JohnBooty]

You're absolutely right.

Power ratings are like, useless^2

There's no great way to measure power output for an amp, surprisingly. The old FTC rating system was something like continuous wattage at a fixed voltage at all audible frequencies. This was decent, although actual music isn't anything like white noise. =)

So manufacturers give absolute BS "power ratings" like "40W" which usually means the amplifier can produce that much output, at a single frequency, for a zillionth of a second at 10% distortion which doesn't much resemble real music either.

But even if they were truthful about the rest of that, it wouldn't matter because knowing the power output of the onboard amp is useless without taking into account the efficiency of the speaker drivers themselves.