CPUs are complicated pieces of technology. During the manufacturing process, some parts have a better quality grade than others. The better quality parts allow some overclocking without producing errors and therefore they get put into the overclockable K-processors. The worse parts get put into non-overclockable processors and run fine using the default voltage.
Some of the non-overclockable cpus might work fine after overclocking, some might not. Intel definitely doesn't want the negative press when some kids decides to overclock their non-K CPU and break it during the process. So I understand the decision.
Some of the non-overclockable cpus might work fine after overclocking, some might not. Intel definitely doesn't want the negative press when some kids decides to overclock their non-K CPU and break it during the process. So I understand the decision.