A native of Brooklyn, New York City where he attended Canarsie High School in Brooklyn, New York, he played high school football for the Chiefs under coach Mike Camerdese and graduated in 2001.
As a senior, he was moved to linebacker, collecting 98 tackles, 12 sacks, 4 fumble recoveries and 3 interceptions.
Williams was named USA Today 1st team All American and awarded Gatorade Player of the Year in 2000-01 (NY).
As a junior in 2004, he was a Butkus Award finalist and was considered the heir apparent to Jonathan Vilma.
He started at middle linebacker in the season opener against Florida State University, making 3 tackles before suffering a hand injury.
He started in every game at middle linebacker, posting 54 tackles (3.5 for loss), 2 pass defensed and one fumble recovery.
He contributed to the team ranking fourth in the nation in total defense, allowing 270.1 yards-per-game.
[4] As a rookie, he played in 16 regular season games with 3 starts, registering 37 tackles, one sack, 2 quarterback hurries, 16 special teams tackles (fourth on the team), 2 passes defensed and one forced fumble.