Abstract: A system and method for initializing deterministic source-synchronous transfers between devices in a computer system using one or more ratio bits to indicate a ratio between clocks. In an exemplary computer system, one or more processors are each coupled to a bridge. The one or more ratio bits are used to indicate a ratio between the system clock of a first device, such as a processor, and the system clock of a second device, such as the bridge. Each device may also operate at a multiple of its system clock. Once the one or more ratio bits have been stored, the first device can determine when edges of its operating clock correspond to edges of the operating clock of the second device. The use of the one or more ratio bits may advantageously allow devices in the computer system to operate on different system clocks without dedicated signal lines or pins to indicate the frequencies of those different system clocks.