Method and apparatus for maintaining load balance on a graphics bus when an upgrade device is installed

摘要

An embodiment of a graphics device that maintains load balance on a graphics bus when an upgrade graphics device is installed is disclosed. The embodiment includes load balancing buffers for the strobe compliment signals AD_STB0#, AD_STB1#, and SB_STB# on a 2x mode AGP graphics device. The load balancing buffers couple the 2x mode AGP graphics device to the strobe compliment signals AD_STB0#, AD_STB1#, and SB_STB#, but the load balancing buffers are not connected to any internal circuits within the 2x mode AGP graphics device. The load balancing buffers provide equal capacitive loading between the strobe signals AD_STB0, AD_STB1, and SB_STB and their compliment signals AD_STB0#, AD_STB1#, and SB_STB# when an upgrade 4x mode AGP graphics device is installed.