Which is the right "burn in" method ?

[core13]

After some snooping around I found 3 burn in methods :
Run the CPU for week, month ...
1) at default speed and voltage.
2) at highest stable speed and lowest voltage.
3) at highest stable speed and highest voltage.

which do you think is better?

[dimmreaper]

There isn't one! :O

However I practice #2 for a few days running burn (available in the utilities section on the front page).

I would stay away from that #3, unless you don't care if the CPU burns up.