To my knowledge, "burning in" has nothing to do with making a system more stable after time. You do it to make sure that the system will be stable after extended use and also to test the new hardware to make sure it's not defective. I've never heard of anyone who was having trouble only to have the problems disappear after burning in the hardware. In fact, if you're having that sort of trouble with 100 on the fsb, I would avoid running it at that setting.
Intel i5-2500K 3.3GHz
Asus P8Z68-V Pro/Gen3
8GB G.Skill RipJaws DDR3 1600
EVGA GTX 570 HD 2560MB
Crucial M4 128GB SSD
Corsair HX 620W
Win7 Pro 64-bit SP1
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