I've searched for "overclocking" and found a few posts, including one from Atmel Norway saying don't do it, it's very naughty :twisted:.
BUT, there are different sections of the MPU which may cope differently with higher clock rates. When I get a bit of spare time, I was going to test a Mega88 at increasing clock speeds, testing if possible where problems start to crop up.
The data sheet says: "The calibrated RC Oscillator is used to time Flash (and EEPROM) accesses." so perhaps increasing clock speed does not affect Flash or EEPROM programming.
My guess is that it would be the CPU which would stand the most overclocking, and that the peripherals such as USART, ADC etc. will start to fall over first. Has anyone else done any experiments?
I don't need to overclock anything right now, but I was just curious as to how much "headroom" there might be.