It might have stayed afloat or stayed afloat a little longer. That is, if the iceberg did not have an underwater extinsion that did not pierce the ship underneath the hull.

If you will remember, there was testimony that some people saw water seeping up from the floor plates in boiler room (I think 5 or 4), something like six feet from the keel. This means that there was likely ice actually hitting underneath Titanic, not just on the starboard side like we usually associate with the iceberg damage.

Therefore, if the Titanic rammed the berg head on, there is the possiblility that the ship might hit more of this "under the ship portion" of the berg, and that could have ripped open more further back compartments from the bottom.