Barry Sanders college stats probably would have been better had he not been backing up Thurman Thomas, but he did not rush for more than a 1000 yards until his junior year.
http://www.sports-reference.com/cfb/players/barry-sanders-1.html
Jim Brown did not rush for more than a thousand yards in any in any of his college years, but those numbers are probably skewed because they only played 8 games a year.
http://www.sports-reference.com/cfb/players/jim-brown-1.html
OJ Simpson could also have probably rushed for more than 1000 yards all four seasons if played at USC, but he went to CCSF for the first two before going to USC. His stats at USC were still amazing, though.
http://www.sports-reference.com/cfb/players/oj-simpson-1.html
There were no other players who I could find who could fill your criteria (granted there may be more, but I'll save that for some one else to look up), Marshall Faulk and Tony Dorsett both rushed for more than 1000 yards in each of their college years, but they did not play in power 5 conferences. Most of the other great NFL (let' s say rushed for more than 1500 yards in a NFL season, but other numbers could be added to that, for example Marshall Faulk's receiving yards) running backs I looked up did not fill your criteria because they were back-ups to other good to great running backs, went to JC before FBS, or did not play enough for whatever reason to get the yardage. Marcus Allen, Frank Gore, Shaun Alexandar (greater than 1500 yards twice), LaDainian Tomlinson (greater than 1500 yards three times), Eric Dickerson (greater than 1500 yards four times), OJ Simpson (greater than 1500 yards three times), etc., etc.
So in short all it takes is "To start as a true freshmen in a power 5 conference, run for over 1,000 the first 3 years, never miss a game, then enter the draft at 20/21" to become a serviceable to good NFL running back (Darren McFadden), to become a great one takes even less according to your criteria if followed strictly. How many first round busts have there been that had great college careers, Blair Thomas, Curtis Enis, Ki-Jana Carter, and Trent Richardson come to mind. So you are correct, college success does not equal NFL success.