They don't. And don't tell them. Just continue to use the stock Intel heatsink. You're covered for 3 years. Just keep your receipt in a safe place. I used Intel's warranty once, and they got me a new cpu in about 6 days. But don't assume the cpu is bad. Cpus don't die unless you apply too much voltage. Intel has built in protection that slows down the cpu automatically when it's too hot to prevent damage.