System hangs on

I have a program using CUDA under Visual Studio 2005.
while running ANY device function the system (Windows Server 2003 x64) completely hangs on. It doesn’t respond to anything (mouse, ctrl+alt+delete). The only way is to wait until it finishes computations or reboot the machine if it’s not finishing due to some reasons! :angry:
Is there any way to stop GPU computations (like for CPU break all command in VS 2005 or simple ctrl+alt+delete and terminate process)?
Videocard is Quadro FX 4600. Driver’s version 169.21.
Thanks in advance.

This is expected behavior. When the kernel is running, it uses 100% of the graphics hardware meaning the graphics on the screen cannot be updated. If your kernels run for ~1s, there will be a lot of lag to respond to input.

No one kernel should hang for more than 5s, though as there is a watchdog timer. Check for errors after every cuda call and exit your program if you encounter any.

Another option is just to press ctrl-C (command line programs only). After the current kernel completes, the ctrl-C should take effect and kill your app.