BF4 freezes and windows reports error: AppHangB1

While playing, and with no common action or area, the game will freeze with about a one second audio loop. The only way out is to Ctrl+Alt+Tab and end the program with task manager. At that time, Windows reports the error to be "AppHangB1" and the program to be bf4.exe, along with various other statistics.  Sometimes this happens after a couple of hours of gameplay, sometimes after 5 seconds. Any ideas?

Win7 64-bit

AMD 965BE

Foxconn Destroyer mobo

8GB Corsair Dominator

nvidia 460 with 1GB DRAM

nvidia 9800GTX+ for Physx

WD 300GB VelociRaptor

PC Power & Cooling 1200W