Standalone Atmega chip

Hi everyone.

I have Arduino Uno R3 developer board and I need to run it's Atmega328P (DIP28 package) chip separately in 3.3V, 8MHz to decrease power usage. Is it possible?

I also tried to programm Arduino Pro Mini in this mode and result was success. But there was not only Atmega. I want to run it on fully stand-alone mode. Any ideas?