Hi Everyone, I got hold of the 5,1 3.3 and have installed an EVGA GTX680 and 48GB of RAM (of which 32GB is working - one of the sticks appears to be deadski...). Have installed NVIDIA Web Driver 313.01.02f01. Running the Amira 5.5 Beta, Amira didn't initially detect the 680 as a CUDA device, so I went through the Install Process for the CUDA 5.0 drivers and Toolkit. http://docs.nvidia.com/cuda/cuda-getting-started-guide-for-mac-os-x/ When I run deviceQuery, my output differs to that in the installation guide in one area - at the end I have: deviceQuery, CUDA Driver = CUDART, CUDA Driver Version = 5.0, CUDA Runtime Version = 5.0, NumDevs = 1, Device0 = GeForce GTX 680 I don't get the next line, which in the user guide is: [deviceQuery] testresults... PASSED Similarly, in bandwidthTest I do not get the last line: [bandwidthTest] testresults... PASSED The particles sample works well despite this - ~430fps. Amira, however, brings up an 'unspecified launch error' whenever I try to run a CUDA-accelerated filter using the GTX (which is now listed in the CUDA device drop-down). Another thing I noticed is that the driver versions in the CUDA preferences (313.01.02f01) and CUDA-Z (310.40.00.05f01) do not seem to match? Any ideas? Should I be using OS X Default instead of the nvidia web driver? Is the presence of the dodgy DIMM having an effect?