FWIW, I'm attaching the screenshot mentioned by Diederik to this mail, as the shared link will expire sooner than later. (and, in case somebody comes across it -- the units given to cpupower should be given in KHz, for some reason -- that is, "700000" or "1000000", not "700" or "1000" as the image shows)
Attachment:
rpi0_1GHz.png
Description: PNG image
