What does FSB (front side bus) mean, and is it important when planning a motherboard purchase?
Computer Doctor: FSB is just another name for the motherboard speed, or the speed of the socket or slot that the processor is plugged into. It is also called the system bus. The term FSB started with the Pentium Pro, which was the first processor to move the L2 cache into the processors and run it on a separate bus from the main system bus. Intel called this DIB (Dual Independent Bus) architecture. Since the cache bus was sometimes called the back-side bus, people started calling the system bus the front-side bus. See page 86 (12th edition) for more information on DIB. It’s important to consider FSB speeds when planning a motherboard purchase because the speed of the FSB is the speed of the motherboard, and also the speed of the bus that the processor is plugged into. As with computer-related factors, the faster the FST the better. For example, compare two Pentium III 800MHz systems. The PIII 800 can be set up to run at either an 8x multiplier on a 100MHz FSB, or at a 6x multiplier on
