I've got the pre-Pascal Titan X (compute capability 5.2) on a workstation running Ubuntu 14.04 and CUDA 7.5. BOINC works with SETI@Home, but GPUGrid yields nothing but computation errors. Any thoughts?

I'm able to use the GPU for other CUDA apps, and the driver is working fine. Only GPUGrid complains.

Trying to run acemd directly:
$ ./acemd.848-65.bin
# ACEMD Molecular Dynamics Version [3212u2]
# CUDA Synchronisation mode: BLOCKING
# Unable to initialise. Check permissions on /dev/nvidia* (err=-1)
$ ls -lah /dev/nvidia*
crw-rw-rw- 1 root root 195, 0 Aug 31 10:10 /dev/nvidia0
crw-rw-rw- 1 root root 195, 255 Aug 31 10:10 /dev/nvidiactl
crw-rw-rw- 1 root root 195, 254 Aug 31 10:10 /dev/nvidia-modeset
crw-rw-rw- 1 root root 247, 0 Aug 31 10:10 /dev/nvidia-uvm
$ nvcc --version
nvcc: NVIDIA (R) Cuda compiler driver
Copyright (c) 2005-2015 NVIDIA Corporation
Built on Tue_Aug_11_14:27:32_CDT_2015
Cuda compilation tools, release 7.5, V7.5.17
$ nvidia-smi
Mon Sep 12 18:17:44 2016
+------------------------------------------------------+
| NVIDIA-SMI 364.19 Driver Version: 364.19 |
|-------------------------------+----------------------+----------------------+
| GPU Name Persistence-M| Bus-Id Disp.A | Volatile Uncorr. ECC |
| Fan Temp Perf Pwr:Usage/Cap| Memory-Usage | GPU-Util Compute M. |
|===============================+======================+======================|
| 0 GeForce GTX TIT... Off | 0000:04:00.0 On | N/A |
| 22% 48C P8 17W / 250W | 200MiB / 12283MiB | 0% Default |
+-------------------------------+----------------------+----------------------+
$ uname -a
Linux vader 3.13.0-95-generic #142-Ubuntu SMP Fri Aug 12 17:00:09 UTC 2016 x86_64 x86_64 x86_64 GNU/Linux

Thoughts?

You should check the access rights of the user who runs BOINC manager on that folder. (The command prompt runs under a different user)

The boinc user runs the boinc background process & SETI@Home. My account runs the Boinc Manager, and doesn't have rights to the Boinc data directory. Is that the problem? Why would the user of the Boinc Manager need access to the Boinc data directory? This works fine for SETI@Home for CPU & GPU tasks.