I have a pretty strange problem with one of our applications. The application is a .Net+WinForms application, it uses SlimDX to access DX9 and DX11 interface to do some 3D rendering. Recently, for unknown reason, the application always stops for about 4 seconds when it tries to create the second Device object ( for DX9 or DX11 interface). The applications doesn't stop at the first time or any time after the second device object. The problem happens regardless whether the application creates DX9 device or DX11 device; I have checked with a GPU monitor, the GPU and the CPU are not having high load during this 4 seconds. Also, I have not changed our SlimDX or DirectX library, but the OS (Windows 7) could have been changed by regular Windows OS update.

Has anybody had experience with this kind of problem? I would appreciate very much any advice to track down this problem.

thanks in advance.

Thanks for the message. I have checked potential deadlocks in the code and can not find any such problem. I could avoid the apparent blocking by create a second dummy Device object from a separate background thread, but this is really a dirty work-around.

Thanks Max. I indeed got the graphic card driver updated recently. The graphics driver is NVidia, 04/04/2014; version 9.18.13.3523; My hardware is: AMD Phenom 1045T (CPU); 2.7 GHz. Nvidia GeForce GTX 650. I have just tried the software on a different machine (with different graphics card) and the the problem did not happen on that machine. So, there seems to be hardware or driver related issue with my computer.