Without 3 they are not a dynasty other than an ACC dynasty. Otherwise Florida was a dynasty from 2006-2008.
Clemson in the past 4 years:
2015 - 14-1, won ACC, lost in title game
2016 - 14-1, won ACC, won title
2017 - 12-2, won ACC, lost in semis
2018 - 15-0, won ACC, won title
Florida 2005-2008
2005 - 9-3, 2nd in division
2006 - 13-1, won SEC, won the title
2007 - 9-4, 3rd in division
2008 - 13-1, won SEC, won the title
Florida was good, but you don't fail to win 10 games 2 times in 4 years and get called a dynasty. Plus Florida had Tebow. Clemson has won titles with 2 different QBs.
That's what makes Saban's run the most impressive - he's doing it with so many different guys at QB.