As to my problems with this cuda computer, which started with upgrading to the nvidia driver 275.09.01-1, other people have my same feeling that there is no hardware problem (someone had raised doubts that a crossfire can't support more than one nvidia card, while SLI is not needed for cuda), possibly a driver problem.
My question is (please, see below) how to try to resolve the puzzle, by either taking the latest driver from "unstable" or back to the older 270.41.19-1 driver. I have no experience in doing either move safely. Thanks for advice francesco pietra Originally Posted by chiendarret View Post Also, before current nvidia driver 275.09.01-1, I worked for a week with 270.41.19-1 without any warning. That makes me think its just an issue with the 275.09.01-1 driver, not your hardware. You could try getting the drivers from 'sid' (currently 275.09.07-5), or maybe even experimental if you were game. Or you could manually install 270.41.19 drivers. There might even be aq way to rollback to the 270.41.19-1 drivers as well, but I dont know how.....if its even possible. ---------- Forwarded message ---------- From: Francesco Pietra <chiendar...@gmail.com> Date: Sat, Jul 9, 2011 at 12:04 AM Subject: Fwd: about latest nvidia cuda driver 275.09.07 To: amd64 Debian <debian-amd64@lists.debian.org> Under certain circumstances, especially if the CUDA machine is shutdown or reboot by commands from a ssh-linked desktop, problems vanish. I begin to suspect that the combination of mutithreading with the two gtx-470 cards may find problems with the "composite" extension of X11. When VMD (an OpenGL viewer CUDA accelerated) is launched from a gnome terminal it says: Multithreading, 6 processors Available two CUDA accelerations Detected X11 "Composite" extension:if incorrect display occurs, try disabling this optional X server feature OpenGL renderer GeForce gtx 470/PCI/SSE2 Full GSL rendering mode available In this case there were no problems in using VMD with a 8GB file, using many of its features (removing water, calculating RMSD, making movie of the MD trajectory, etc. What happens - i.e, what is left available - if "composite" extension is disabled I have not tried. francesco ---------- Forwarded message ---------- From: Francesco Pietra <chiendar...@gmail.com> Date: Thu, Jun 30, 2011 at 10:21 AM Subject: about latest nvidia cuda driver 275.09.07 To: amd64 Debian <debian-amd64@lists.debian.org> Following kind guidance by Lennart Sorensen as to the correct installation of the nvidia driver, I recently got a two GTX-470 computer work perfectly for molecular dynamics simulations with NAMD-CUDA. The simulations were launched from linux terminal, without calling the X server. Command (as root) nvidia-smi -L was first needed to activate the GTX 470 cards (udev normal affair) ******************** On 27Jun the system was upgraded from driver 270.41.19 to 275.09.07. On rebooting, dkms did its job for the existing headers 2.6.38-2. However, now the above NAMD-CUDA MD launching does not work any more. Sincerely I can't say if the crash described below occurred immediately after the driver upgrading, but the dates are very close. Now, on launching MD as above described, the system hangs, the screen shows blinking characters and letters, and the power must be shut down. The log of the simulation says CUDA error cudaStreamCreate on P2 0 which is a normal message of NAMD when the graphic boards are not seen. However, the computer should not hang. Launching NAMD-CUDA from a terminal window of gnome-2, the procedure runs correctly. I understand that this report fails to analyze correctly what happens. It is a simple warning to see if other amd64 users had problems with the new nvidia driver. thanks francesco pietra -- To UNSUBSCRIBE, email to debian-amd64-requ...@lists.debian.org with a subject of "unsubscribe". Trouble? Contact listmas...@lists.debian.org Archive: http://lists.debian.org/CAEv0nmvCFPLRPrqaV5zdo6+f-te6WbwpO-udsuR6P0y4rwM=0...@mail.gmail.com