Hi -
Can you upload a copy of your DXDIAG? Also when you CPU froze how long did you wait before using the Task Manager? Finally, If you can open Windows Event Viewer and find the Critical or Error that corresponds to the timeframe of the engine freeze and save out that event (or events if you cannot determine which one) and upload that here as well. You will have to zip those event file(s) as the file type is not recognized by AnswerHub.
Thank You
Eric Ketchum