If Ye're Over-clucking it's impossible to say-- but the harder you push things --the more cooling you need....the shorter the life-expectancy.
More Speed = more HEAT
Heat must be removed--and even that has it's limits.
Sometime you'll start hitting what's known as "bottlenecks" --for example-- your FSB can only be opened so wide. Your
RAM timings have physical limits. Your P3 can only Cycle so many thousand times per sec.
All of this stuff produces more heat-- amd heat is a killer. That's what OC is all ablout --seeing how far you can push it before she blows ....
"I need more power Scotty"
I canna poosh em enny harder Cap'n .....the Dilithium Crystals are gonna blow !!