I do realize this is years old, but I have the same issue and have solved it. I have a 44 Core Xeon machine (22 physical cores and 22 hyperthreaded for a total of 44). Many of these older games don't manage this many cores well and actually will run faster/better with some cores disables. My previous machine was a dual Xeon with 12 cores per processor for 24 total and no games had issues, thus I approximated that. Using msconfig, under "Advanced Option" button, I limited the machine to 22 cores (the physical number) and voila! it runs fine! This was also true for Far Cry 4 to even load. Once cores dropped, it runs fine.
Great answer, this helped me as well! Also running a "44" core xeon now.
