[kube-system]

It's mostly a matter of matching the output characteristics of the amplifier to the capability of the speakers... which is what most consumer products with speakers do. Note that the OP concluded that it likely wasn't possible to blow the PC speaker.

[throwaway789657]

If you have your own receiver and your own speakers--a home stereo system, not a PC speaker system--it is just a matter of turning the nob too high to blow them out. With all these wifi-connected receivers these days, I bet if your laptop is compromised, a hacker could turn up the volume and physically damage your speakers. Anyone inside your wifi can cause many thousands of dollars (or whatever your speakers cost) of physical damage. Wow!