3 times a week is fine, it depends on overall volume, how many sets for chest are you doing total in one week?
Have you taken a week off since you started lifting?
Out of incline, decline flat, db and bb what are you doing most and what are you doing least?
Anyway, I suggest about 9 sets of bench all up for the total week, dont goto failure.
If you havent, take a week off.
whatever your doing most and least swap it around, I would favour DB over BB maybe try decline and slight incline and stick with those 2.
If you think its your triceps holding you back start doing decline skullcrushers.
Also check out testosterone nation's articles on benching, theres a wealth of infomation there on improving your bench.