when my program runs to HRESULT hResult = PDIRECT3D->CreateDevice(0,D3DDEVTYPE_HAL,g_hWnd,m_D3DCREATE_MULTITHREADED|D3DCREATE_MIXED_VERTEXPROCESSING,&m_PresentationParam,&m_pD3DDevice); then my computer reset. does anybody know why??? if you know any possible reason, plz tell me~!! thanks a lot

Most likely a problem with your video card driver but if you could post what values are you filling in for the presentation parameters there may be a problem there.

Presentation parameters I set is here:

PresentationParam.BackBufferWidth = pMode->Width;
PresentationParam.BackBufferHeight = pMode->Height;
PresentationParam.BackBufferFormat = pMode->Format;
PresentationParam.BackBufferCount = 1;
PresentationParam.MultiSampleType = D3DMULTISAMPLE_NONE;
PresentationParam.SwapEffect = D3DSWAPEFFECT_COPY;
PresentationParam.hDeviceWindow = g_hWnd;
PresentationParam.Windowed = TRUE;
PresentationParam.EnableAutoDepthStencil = TRUE;
if ( pMode->Format == D3DFMT_A8R8G8B8 || pMode->Format == D3DFMT_X8R8G8B8)
{
PresentationParam.AutoDepthStencilFormat = GetDefaultDepthStencilFormat(32,8);
}
else
{
PresentationParam.AutoDepthStencilFormat = GetDefaultDepthStencilFormat(16,0);
}

PresentationParam.Flags = D3DPRESENTFLAG_LOCKABLE_BACKBUFFER; PresentationParam.FullScreen_RefreshRateInHz = D3DPRESENT_RATE_DEFAULT;
PresentationParam.PresentationInterval = D3DPRESENT_INTERVAL_IMMEDIATE;

I think what I fill is ok.
The problem only happened on 5700.
TNT2, Geforce2, Geforce4 are all ok.

Thanks for your reply, I'll try.