The ICS9148-17 generates all clocks required for high speed RISC or CISC microprocessor systems such as Intel PentiumPro or Cyrix. Eight different reference frequency multiplying factors are externally selectable with smooth frequency transitions. Features include four CPU, six PCI, two AGP (=2xPCI) and Twelve SDRAM clocks. Two reference outputs are available equal to the crystal frequency. One 48 MHz for USB, and one 24 MHz clock for Super IO. Built in 1.5%, 0.6% center or down spread spectrum modulation to reduce EMI. Serial programming I2C interface allows changing functions, stop clock programing and frequency selection. Additionally, the device meets the Pentium power-up stabilization, which requires that CPU and PCI clocks be stable within 2ms after power-up.