As we discussed it in this question, the Death Star can deliver a mind-boggling amount of energy. If it is capable of blowing up an Earth-sized planet, this means the equivalent of the annihilation energy of over 1,200,000,000,000 tonnes of antimatter. In comparison, nukes measure on this scale in the gram range (the one used at Hiroshima being under one gram). This means, even if the shot gets a million times weaker due to distance, it is probably still enough to kill all multi-cellular life on a planet.
Regarding this, how much is the maximum effective range of the Death Star? By effective I mean that even if it does not blow up a planet Alderaan-style, it delivers enough damage on a planetary scale to effectively cripple a planet.
Is there any related information in the expanded universe?