Considering how much power have modern microcontrollers there is no surprise what they are capable of. Following project developed by arthurb is based on DSPIC33F128MC804 microcontroller that runs at 80MHz.
The final source isn’t limited by chess engine. There was enough room left for audio, keyboard, serial, VGA video, temperature sensor, RTC analog clock and even game of life. Code is written from scratch and is modular and well commented.