Originally posted by: Dark Cupcake
Actually i've been wondering for while do Athlon 64 cpus have thermal throtling on the chip itself like the P4's.
Cause that was one reason i went for a p4 over an Athlon Xp, heard a few stories of the Athlon deaths syndrome
The roles have reversed now, Prescott based P4's run very hot and tend to overheat, while A64's run nice and cool. Both have built in thermal protection to keep them from burning up.
I've never seen an A64 throttle, but with P4's, throttling(at least TM1, which is built in to the cpu) doesn't actualy change the clock speed. Instead it initiates a duty cycle. For example with 33% throttling, it basicly pauses the CPU 1 out of every 3 clock cycles to give it a rest and try and bring down the temps.
It also drasticly hurts performance. For example, a 3ghz P4 thats throttling, will still be running at 3ghz, so any software that monitors frequency, such as CPUz, won't show anything different, but performance wise, it will be acting like a 2ghz proccessor. Throttlewatch is a program that will show throttling. For a P4 throttling kicks in around 72c at stock speeds. Overclocking lowers the temp at where throttling kicks in, especialy with increases in Vcore.