Williams finished with 58 rushing yards on 16 carries and added 62 receiving yards on five catches as the Red Raiders (7-0, 4-0 Big 12) improved to 7-0 for the first time since 2008.
Davis Webb racked up 462 passing yards on 36-of-50 efficiency with two touchdowns -- both to Jace Amaro, who hauled down nine passes for 136 yards overall.
Bradley Marquez made eight grabs for 112 yards in the win.
The Mountaineers (3-4, 1-3) dropped a second straight as Clint Trickett was held to 27-of-43 through the air for 254 yards and one touchdown.
Dreamius Smith provided two scoring runs for West Virginia.
Justin Bieber crashes Drake Bell's album release party
Chipotle plans first price increase in 3 years