For all that have nine of nines defiant, you may want to try this hardpoint for it, it is based on durandal's 1.0 and 1.1 versions of the defiant. it has side phasers, no front phaser, but the phaser turret on top has a good firing arc.
420 mhz? I wouldn't bother getting a new card, you processor wont handel it anyways.
I have a hardpoint addon that beef's up the power of admirals defiant so it can take out a keldon. (by 9 of 9). It is on BCfiles, shouldn't be too ahrd to find.