800 rms how much pmpo?

800watts RMS is 5,000,000,000watts PMPO. However, if you upgrade to the high viscosity audio cable, you can get as much as 8,000,000,000watts PMPO.

Now, for the series answer.

PMPO has no grounds in science, and you will never find it in any legitimate engineering text. It is a made up value to exaggerate the capability of the audio system for marketing purpose only. So, you are free to make up whatever conversion you want to calculate the PMPO.

Any legitimate audio manufacture will not advertise using PMPO, even the use of Peak Power is iffy. Stay away from any audio equipment advertising PMPO.

For the power value to have any meaning, the manufacture needs to indicate both the power (in watts) and the distortion (in %).