I have just noticied that kernelExecTimeoutEnabled device property is TRUE for all the GPUs in the system, not only for those that have a monitor attached.
Definitely, some time ago kernelExecTimeoutEnabled was TRUE for the GPU with a monitor and FALSE for all others, however, after drivers updgrade or may be after CUDA upgrade this behaviour has changed unexpectedly.
What might the the reason? System config is: Win7 x64, CUDA 5.5, eight GTX 580 GPUs, 320.49 drivers.
Thanks in advance.