331.38 driver on SuSE significantly reduced GPU compute performance vs Windows

I’m having some performance issues using the 331.38 driver with openSuSE 13.1. We’ve got a workstation with a Tesla K40c and a Quadro K6000 which we use for visualization and also GPU compute for dualSPHysics. However, we’ve noticed that the compute performance under Linux is about 50% of that when we run the same jobs under Windows 7. (6 hour job on Windows, 12 hours on Linux) Previously, we had two Quadro 6000s and the Linux performance was always slightly faster than Windows.

Everything seems to be installed correctly, and the clock speed is automatically adjusting for the load. Utilization is about 96%, power hovers around 140W/235W.

Is this a problem with the driver? We’ve tried both Debian 7 and openSuSE with the same issue.

What are you observations? How I can reproduce this issue in-house? Is the system used for both windows and linux is same ?