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Strange D3D11 crash

Hi guys,
I’m not sure if posting this crash is appropriate in the answer hub, since i’m going to give some details about the code, so decided to post here. It all started a couple of weeks ago where anything Unreal would crash right at startup, with no stacktrace at all, I was using 4.5 at that time. I thought it might be an engine bug, so I got lastest code from 4.6 and compile it. Surprisingly, the same issue appeared. So engine bug is ruled out. then Debug build give me a stack trace to WindowsD3D11Device.cpp, method SafeTestD3D11CreateDevice. It crashes at D3D11CreateDevice call. Here is the call stack:


 	0000000000000000()	Unknown
 	nvwgf2umx.dll!00007ffbf6021cfc()	Unknown
 	nvwgf2umx.dll!00007ffbf60e859d()	Unknown
 	nvumdshimx.dll!00007ffc212a1b1d()	Unknown
 	nvumdshimx.dll!00007ffc2129ae5d()	Unknown
 	[External Code]	
>	UE4Editor-D3D11RHI-Win64-Debug.dll!SafeTestD3D11CreateDevice(IDXGIAdapter * Adapter, D3D_FEATURE_LEVEL MaxFeatureLevel, D3D_FEATURE_LEVEL * OutFeatureLevel) Line 156	C++
 	UE4Editor-D3D11RHI-Win64-Debug.dll!FD3D11DynamicRHIModule::FindAdapter() Line 263	C++
 	UE4Editor-D3D11RHI-Win64-Debug.dll!FD3D11DynamicRHIModule::IsSupported() Line 188	C++
 	UE4Editor-RHI-Win64-Debug.dll!PlatformCreateDynamicRHI() Line 40	C++
 	UE4Editor-RHI-Win64-Debug.dll!RHIInit(bool bHasEditorToken) Line 51	C++
 	UE4Editor-Win64-Debug.exe!FEngineLoop::PreInit(const wchar_t * CmdLine) Line 1175	C++
 	UE4Editor-Win64-Debug.exe!EnginePreInit(const wchar_t * CmdLine) Line 31	C++
 	UE4Editor-Win64-Debug.exe!GuardedMain(const wchar_t * CmdLine, HINSTANCE__ * hInInstance, HINSTANCE__ * hPrevInstance, int nCmdShow) Line 110	C++
 	UE4Editor-Win64-Debug.exe!WinMain(HINSTANCE__ * hInInstance, HINSTANCE__ * hPrevInstance, char * __formal, int nCmdShow) Line 191	C++


It leads to nvwgf2umx.dll before causing an access violation, which seems to be nvidia driver. Next step that I tried is to roll back to an older version of Nvidia driver which I believe worked before. Bam, same crash. So I’m a bit confused now. Halp!

The Bug Reports section on Answerhub would be the best place to post this as I believe it’s easier for Epic to assign and track bugs that way, when you do post your bug report over there please attach the output from dxdiag.exe so that Epic can see your exact system configuration.