1. Go into Regedit and determine the current primary display card by looking in HKey_Local_Machine\Hardware/DeviceMap\Video and note the GUID (global unique indentifier assigned by Windows) for the entry "\device\video0" which is the long string at the end of the entry in brackets { }.
2. Edit HKey_Local_Machine\SYSTEM\CurrentControlSet\Control\Video\{guid}\0000, where {guid} is the number derived from the above step.
3. Open the "0000" directory and enter a new key called OGL_ThreadControl and give it a value of 2. This will disable multithreading in the driver for all OGL apps.
4. In the same "0000" directory, to disable driver multithreading for all D3D apps, you can enter WTD_EXECMODEL and give a value of 0.