Hi! New to the boards... came here in seek of a way to run an arduino pro 3.3v (from sparkfun) on 2 AAs. This is important because I'm actually just stealing the power rail from a wireless xbox controller. The two batteries only give me 2.6-2.9 volts, which is only enough to boot the micro on a good day.
I tried running
CLKPR = (1<<CLKPCE);
CLKPR = B00000011;
in my setup loop but it still would not power on with 2 AAs. Are there additional steps or tricks I can try?