Was Augustine a five-point Calvinist? Well, he definitely adhered to the doctrine of Total Depravity:
But, on the other hand, Who would deny this? But it is for that reason we ask not to be led into temptation, so that this may not happen. And if we are heard, certainly it does not happen, because God does not allow it to happen. For nothing comes to pass except what either He Himself does, or Himself allows to be done. Therefore He is powerful both to turn wills from evil to good, and to convert those that are inclined to fall, or to direct them into a way pleasing to Himself (On Perseverance of the Saints, Chapter 12).
Total depravity does not necessarily mean that a man is as bad as he could possibly be. However, it means that his depraved nature is total. He can never of his own will do anything but forsake God and it is in this fashion his depravity is total.
Augustine understood this and further asserted because this is the case, it is necessary for God to convert the will of man form evil to good. Just how God does is not always clear. If you have questions about what the Scripture says about this, we answer those here.