This part is a kind of semiconductor called W164.

Function of this product has Spread Spectrum Desktop/Notebook System Frequency Generator.

Manufacturers : Cypress Semiconductor

Image and pinout :

Some of the text within the PDF file :

W164 Spread Spectrum Desktop/Notebook System Frequency Generator Features • Maximized EMI suppression using Cypress’s Spread Spectrum technology • Reduces measured EMI by as much as 10 dB • I2C programmable to 153 MHz (16 selectable frequencies) • Two skew-controlled copies of CPU output • SEL100/66# selects CPU frequency (100 or 66.8 MHz) • Seven copies of PCI output (synchronous w/CPU output) • One copy of 14.31818-MHz IOAPIC output • One copy of 48-MHz USB output • Selectable 24-/48-MHz output is determined by resistor straps on power-up • One high-drive output buffer that produces a copy of the 14.318-MHz reference • Isolated core VDD pin for noise reduction Key Specifications Supply Voltages:... VDDQ3 = 3.3V±5% VDDQ2 = 2.5 [ ... ]

W164 PDF Datasheet Download