I have a Linux PC (Ubuntu 14.04) with a nVidia GTX 480 GPU. All work units stop after a few seconds and give an "error while computing" message. The same system has completed work units from other BOINC projects that use GPUs. I'm using driver 331.38.Any help will be appreciated. Thank you.

Bill42,

Take a look at this thread and see if it addresses your errors.

http://www.gpugrid.net/forum_thread.php?id=3736&nowrap=true#36577

Hope that helps.

There may also be something else going on, I used to be crunching successfully with Ubuntu 14.04 + custom client 7.3.15 + driver 340.24 (manual install after uninstalling packages nvidia-304 and nvidia-331) + cuda 6.0 application.

Now since this morning, all new tasks downloaded error ! (20 tasks to be precise see : http://www.gpugrid.net/results.php?hostid=177839&offset=0&show_names=1&state=5&appid=)

Error:

<core_client_version>7.3.15</core_client_version>
<![CDATA[
<message>
process exited with code 201 (0xc9, -55)
</message>
<stderr_txt>
# Unable to initialise. Check permissions on /dev/nvidia* (err=100)

</stderr_txt>
]]>

I noticed Ubuntu 14.04 downloaded this morning the following updates that in my understanding shall not have impacted GPUGRID (since I use driver 340 and CUDA libs are provided by GPUGRID app) :
-nvidia-opencl-icd-331-updates (backported from 14.10)
-nvidia-libopencl1-331-updates (backported from 14.10)
-libcuda1-331-updates (backported from 14.10)

I did a sudo apt-get purge of these updated libs, a few tasks downloaded and imediately failed like before... then (around 3-5 minutes after purging the libs) it started to crunch again.

Due to the 3-5 minutes delay, I cannot really say if it's a flow of 20 "bad tasks" or if really, this Ubuntu update was responsible for the tasks erroring...

Will report if I see other errors.

No errors > 24h later, so I guess the errors were generated by the library updates (please note on this computer nvidia-331 and nvidia-331-updates were purged before the issue, so not concerned by automatic updates)

Which one of these three libraries interferes with GPUGRID calculations, and shall be excluded from Ubuntu's updates ? (I would suspect the third one)
-nvidia-opencl-icd-331-updates
-nvidia-libopencl1-331-updates
-libcuda1-331-updates