Thank god I had an extra heat-sink laying around
I bought an extra one one day when my other one in an old tower failed. Long story short, I ended up with an extra because I had bought one by itself, and another came with a CPU I bought for my new machine. I figured I'd keep it as an extra for a "just in case".
Well that "just in-case" happened today. I was rocking out to some tunes when I heard a horrible buzzing sound from my tower. I popped it open to see what it was, then noticed my heat-sink fan was not on. I quickly looked at my temps and they were rising rapidly, and stuff started chunking up bad. I unplugged my tower quickly. I popped the old heat-sink out and popped the extra one in. Everything is A-OK now
An ounce of prevention is worth a pound of cure
Just a thought. Keep an extra one around just in-case. Even if it's just a cheap working one is better then a fried CPU.