(FSB) The bus
via which a processor
communicates with its RAM
; one half of the Dual Independent Bus
(the other half being the backside bus
). The L2 cache
is usually on the FSB, unless it is on the same chip as the processor [example?].
systems, the PCI bus runs at half the FSB speed. Intel
's Pentium 60
ran the bus and processor at 60 MHz
. All later processors have used multipliers to increase the internal clock
speed while maintaining the same external clock speed, e.g. the Pentium 90
used a 1.5x multiplier. Modern Socket 370 motherboards
support multipliers from 4.5x to 8.0x, and FSB speeds from 50 MHz to a proposed 83 MHz standard. These higher speeds may cause problems with some PCI hardware.
Altering the FSB speed and the multiplier ratio are the two main ways of overclocking
Toms Hardware - The Bus Speed Guide (http://www.tomshardware.com/reviews/bus-speed-guide,49.html).
Toms Hardware - The Overclocking Guide (http://www.tomshardware.com/reviews/overclocking-guide,15.html).