Keep in mind that all Athlon64 CPUs have “Cool n’ Quiet” technology. This means when enabled and the CPU is at idle, the core clock will be scaled down to use less energy thereby producing less heat allowing fan speeds to be reduced as well. The way AMD scales the CPU down is by adjusting the CPU’s multiplier. This of course means that all CnQ CPUs from AMD are unlocked, in terms of moving down in integers.
HardOCP Overclocks the A64 3000+ to a 272 MHz Bus
Kyle has just posted an article on HardOCP that shares his experience with taking the Athlon 64 3000+ processor and coupling it with a Abit K8T800 Pro motherboard with a locked AGP/PCI bus. The results are quite impressive, and apparently easy to do.