There are male Windham/Wyndhams both in the United States and around the world who have matching Y-DNA markers to male Wyndhams with proven lines of descent from the John Wyndham who purchased Felbrigg Hall, Norfolk, England in 1450. 

The Windhams From England Family Tree DNA group is devoted to helping male Windham and Wyndhams determine if their Y-DNA matches Y-DNA markers of males with proven descents from Felbrigg, Norfolk, England.