The Arduino (Mini) Board (ATmega328P) runs with 5V at 16 MHz with a RC oscillator. If I want to run it at a lower Vcc (eg 3V), the 16 MHz are out of spec.
I know the formula in the datasheet, however, I am uncertain whether the mentioned clock rate corresponds to the frequency before or after the clock divider.
So I am wondering if the fusebit "Divide Clock by 8" would solve this problem. So externaly the µC would still see 16 MHz but internally the frequency would be 2MHz. Is this inside the specification again at ~3V?