I have not had a DNA test myself, but plan to do so by year-end. I will also look into the FTDNA Wales Project.
The only reference to one David Floyd in my book is that of Floyd of Chelsea, Massachusetts as follows:
In 1909 a book was published by The Mudge Press of Boston, Massachusetts entitled, The Two Hundred and Seventy-First Annual Record of the Ancient and Honorable Artillery Company of Massachusetts, by Rev. Stephen H. Roblin, D.D. On page 107 of chapter “The Gibbons Elm at Winthrop,” was noted Samuel Floyd of Chelsea, Massachusetts. He was born on 6 December 1733 in Chelsea. Information on this Samuel Floyd is as follows:
-Samuel Floyd (Ensign Hugh2, Capt. John1), son of Hugh Floyd, Sr., was born about 1695 and died 4 March 1780. He married Joanna Floyd on 8 February 1727, who was the daughter of John Floyd and Rachel Parker. They were first cousins. Samuel and Joanna bore eleven children: Tabitha (1729), Joanna (1731), Samuel, Jr. (1733), Noah (1735), Joseph (1736), Ezra (1738), Rachel (1739), Nathaniel (1741), DAVID (1742), Nathan (1743) and Benjamin (1745)
-Not likely your David Floyd of Chesapeake Bay, Va.