06-30-2016, 05:11 PM
That could explain it. Can you completely uninstall in one of the windows 7 machines the drivers. Also make sure the OpenCL.dll is removed (I think it will be not uninstalled). Then remove it by hand, reboot, reinstall the driver and see if the behaviour changed. My suspicion is that you had a driver of a different vendor (Intel or AMD) on in before. That one didn't remove the OpenCL.dll and so the new driver didn't overwrite it.