This motherboard supports up to 8 stepper drivers with 9 stepper driver outputs in total; And up to 6 PWM fans and 2 always-on fans with the ability to individually select the voltage rail that will drive each fan. Select from Vin, 12V or 5V. Uses a 32-bit ARM Cortex-M4 series STM32F446ZET6 main control chip with a core frequency of 180MHz.