alt Hacker NewsAlmost none. A long time ago a friend and I did the math for sound, photons (status LEDs), etc and it was a rounding error of 1% or something silly like that.
And that’s ignoring that sound and photon emissions typically hit a wall or other physical surface and get converted back to heat.
It all ends up as heat in the end, just depends on where that heat is dumped and if you need to cool it or not. Most watts end up being even more than the theoretical heat per watt due to said cooling needs.
There is literally no way around the fact that every watt you burn for compute ends up as a watt of waste heat. The only factor you can control is how many units of compute you can achieve with that same watt.
Well, at least until somebody devises a system that transports or projects it so that the heat ends up somewhere not-Earth. It'd still be heating the universe in general, of course, even in the form of sprays of neutrinos.
That reminds me of a sci-fi book, Sundiver by David Brin, where a ship is exploring the sun by firing a "refrigerator laser" to somehow pump-away excess heat and balance on the thrust.