<t>Just to clear things up.. Joshua is trying to run benchmarks on some of the machines in our group. We have two GPU-centric machines, one has a GTX 480 and a Radeon 5970, the other has two GTX 480s and an older nVidia card (hence the 9600M). Both machines are running Ubuntu 10.04. Both machines ha...

<t>I did a quick evaluation of OpenMM 2.0/OpenCL/nVidia/ATI and wanted to share the results. I performed a short (100ps) simulation of a small (249 atom) protein with openmm enabled gromacs. I have two high-end video cards, an nVidia GeForce GTX 480 and an ATI Radeon 5970, and an Intel Core i7 3.33G...

<t>It seems to be using the nvidia opencl library. The errors generated by the failing tests are:<br/> dkoes@quasar:~/build/build_openmm$ ./TestOpenCLGBSAOBCForce<br/> exception: Error initializing context: clCreateContextFromType (-2)<br/> dkoes@quasar:~/build/build_openmm$ ./TestOpenCLEwald<br/> e...

<t>I should mention that I'm compiling the 2.0 release on the same machine and the failures I get are:<br/> 52 - TestOpenCLGBSAOBCForce (Failed)<br/> 57 - TestOpenCLEwald (Failed)<br/> 61 - TestOpenCLCustomHbondForce (Failed)<br/> 67 - TestOpenCLNonbondedForce (SEGFAULT)<br/> 69 - TestOpenCLCustomAn...

I suspect the problem with the OpenCL tests is that this machine has both an ATI and an nVidia card in it. How do you control which card the opencl tests run on?

A large part of the problem was that the nvidia.icd was not installed in /etc/OpenCL/vendors. I don't know why the nvidia installer didn't put it there, but manually extracting it from the nvidia installer (-x) and copying it to the location helped.

I have a Galaxy GTX 480 and zephyr/openmm work fine. Previously I had a GTX 260. The performance improvement is about 20-50%, which is somewhat disappointing considering the difference in technology. However, with the 260 I was having all sorts of heat issues that went away with the 480.

<t>The problem (or at least part of the problem) seems to have been with my setup. The geforce 260 was a second video card in my system and was not actually driving any monitor (I was just going to use it for CUDA). Now that I have it setup to drive a monitor, I get much more consistent results.<br/...

<t>Changing nstxout and nstlog doesn't seem to have any effect. Switching to Reaction-Field can have a significant impact though (can be as fast as the CPU).<br/> <br/> However, as I investigate this further, I think I have problems unrelated to openmm since I am getting a wide range of performance ...

<t>Hi Peter,<br/> <br/> Thanks for your response. mdrun-openmm is reporting that it is using CUDA (device 0 to be precise). The CPU is an Intel Core i7 975 at 3.33 Ghz and the graphics card is a 1GB GeForce GTS 250 clocked at 1.78Ghz with CUDA driver 2.3. <br/> <br/> Below is the full mdp file. Most...