Patent ID: 7483031

Claim:
A method for synchronizing two or more graphics processing units, comprising: receiving a clock signal from a clock generator of a first graphics processing unit (GPU) and an external synchronization signal; determining whether the phase of the clock signal and the phase of the external synchronization signal are synchronized; adjusting the frequency of the clock generator to the frequency of the external synchronization signal if the phases of the clock signal and the external synchronization signal are not synchronized to generate a synchronized timing signal; transmitting the synchronized timing signal to a second graphics processing unit (GPU); and producing an image for synchronous output to multiple displays using the synchronized timing signal, including the steps of: generating a first portion of an image in the first graphics unit and generating a second portion of the image in the second graphics processing unit such that the first portion and the second portion synchronously form the image, and transmitting the synchronized timing signal to the first graphics processing unit and the second graphics processing unit in response to the clock signal and the synchronization signal being in phase to control the generation of the first and second image portions.