The code I use right now for setting up OpenGL works just fine on my system. But recently I noticed that when I run it on another, much slower system (300 Mhz Celeron with onboard graphics chip), I can only run in windowed mode, not in fullscreen. Since I only want to run on my system for the time being, it is not that bad, but eventually I''ll want to get rid of this problem. I think it is rather strange the program runs on other, faster systems. I have no clue about what can be wrong, so any suggestions will be highly appreciated, as usual See you!

Do you use the code from a lesson ? If so, which lesson ?

Also, I''d recommend the standard thing : download the latest drivers for your video card.
We should create an acronym for this, shouldn''t we ?

What graphics card does the other (slower) machine have? And you''d need to post the window creation code etc for anyone to help you!

here is the code for my window creation function:

  int COGLWnd::CreateGLWnd(void){	InitGLWnd();								// initialize necessary parameters	DWORD GLe_dwStyle;							// window style	DWORD GLe_dwExStyle;						// window extended style	unsigned int GLe_PixelFormat;				// pixel format	if (!RegisterClass(&WndClass))				// try to register the window class	{		if (GLe_ErrorMsg)		{			MessageBox(	NULL,"Could not register WndClass.",						"Error creating the window!",						MB_ICONEXCLAMATION | MB_OK	);		}		return 1;	}	if (GLe_Fullscr)							// if fullscreen mode requested	{				DEVMODE dmScreenSettings;				// store screen settings in here		memset(&dmScreenSettings,0,sizeof(dmScreenSettings));												// clear the memory		dmScreenSettings.dmFields = DM_BITSPERPEL | DM_PELSWIDTH | DM_PELSHEIGHT;												// flaggs for members that are initialized		dmScreenSettings.dmBitsPerPel = GLe_Bits;													// set number of bits per pixel		dmScreenSettings.dmPelsWidth = GLe_WndWidth;													// set width		dmScreenSettings.dmPelsHeight = GLe_WndHeight;													// set height		dmScreenSettings.dmSize = sizeof(dmScreenSettings);												// set the size of the struct		if (ChangeDisplaySettings(&dmScreenSettings, CDS_FULLSCREEN) != DISP_CHANGE_SUCCESSFUL)		{										// try to change display settings				if (GLe_ErrorMsg)					// if errormsg required...			{				MessageBox(	NULL, "Error changing display settings.",							"Error creating window!",							MB_OK | MB_ICONEXCLAMATION	);													// pop up error message			}			return 2;							// error code for unsuccessful settingchange		}		GLe_dwStyle = WS_POPUP;					// no borders around a pop-up, we need that!		GLe_dwExStyle = WS_EX_APPWINDOW;		// force window on taskbar		ShowCursor(FALSE);						// hide the cursor	}	else										// if windowed mode requested	{		GLe_dwStyle = WS_OVERLAPPEDWINDOW;		// create overlapped window		GLe_dwExStyle = WS_EX_APPWINDOW | WS_EX_WINDOWEDGE;													// make raised edge around appwindow	}		AdjustWindowRectEx(&WndRect,GLe_dwStyle,FALSE,GLe_dwExStyle);												// adjust the window size	if (!(GLe_hWnd = CreateWindowEx(	GLe_dwExStyle, GLe_WndClass,											GLe_Title, GLe_dwStyle | WS_CLIPSIBLINGS | WS_CLIPCHILDREN,										0, 0,										WndRect.right-WndRect.left, 										WndRect.bottom-WndRect.top,										0, 0,										GLe_hInstance,										0	)))												// create the window requested	{		KillGLWnd();							// kill GL window		if (GLe_ErrorMsg)						// if errormsg required...		{			MessageBox(	NULL, "Error calling CreateWindowEx.",						"Error creating the window!",						MB_OK | MB_ICONEXCLAMATION	);														// pop up error message if required		}		return 3;								// error code for creating the window	}	if (!(GLe_hDC = GetDC(GLe_hWnd)))			// try to get a Device Context	{		KillGLWnd();							// kill GL window		if (GLe_ErrorMsg)						// if errormsg required		{			MessageBox(	NULL, "Could not get a Device Context.",						"Error creating the window!",						MB_OK | MB_ICONEXCLAMATION	);														// pop up message		}		return 4;								// error code for getting a DC	}	if (!(GLe_PixelFormat = ChoosePixelFormat(GLe_hDC,&GLe_pfd)))			{											// try to find a pixel format		KillGLWnd();							// kill GL window		if (GLe_ErrorMsg)						// if errormsg required		{			MessageBox(	NULL, "Could not find a pixel format.",						"Error creating the window!",						MB_OK | MB_ICONEXCLAMATION	);														// pop up message		}		return 5;								// error code for finding a pixel format	}	if (!(SetPixelFormat(GLe_hDC,GLe_PixelFormat,&GLe_pfd)))				{											// try to set the pixel format		KillGLWnd();							// kill GL window		if (GLe_ErrorMsg)						// if errormsg required		{			MessageBox(	NULL, "Could not set the pixel format.",						"Error creating the window!",						MB_OK | MB_ICONEXCLAMATION	);														// pop up message		}		ProgEnd = true;		return 6;								// error code for setting the pixel format	}	if (!(GLe_hRC = wglCreateContext(GLe_hDC)))													// try to create a Rendering Context	{			KillGLWnd();							// kill GL window		if (GLe_ErrorMsg)						// if errormsg required		{						MessageBox(	NULL, "Could not create a Rendering Context.",						"Error creating the window!",						MB_OK | MB_ICONEXCLAMATION	);														// pop up message		}		return 7;								// error code for creating RC	}	if (!(wglMakeCurrent(GLe_hDC,GLe_hRC)))		// try to activate RC	{		KillGLWnd();							// kill GL window		if (GLe_ErrorMsg)						// if errormsg required		{			MessageBox(	NULL, "Could not activate the Rendering Context.",						"Error creating the window!",						MB_OK | MB_ICONEXCLAMATION	);															// pop up message		}		return 8;								// error code for activating RC	}	ShowWindow(GLe_hWnd, SW_SHOW);				// show the window	SetForegroundWindow(GLe_hWnd);				// set window to the foreground	SetFocus(GLe_hWnd);							// set focus to the window	ResizeGLWnd(GLe_WndWidth,GLe_WndHeight,GLe_Perspective);	InputSys = new CInput;						// create new input system object	if (!InputSys->Init(GLe_hWnd,GLe_hInstance,I_KEYBOARD))	{											// try to initialize input system		if (GLe_ErrorMsg)		{										// pop up message			MessageBox(	NULL,"Error initializing the input system.",						"Error calling InputSys->Init !",						MB_ICONEXCLAMATION | MB_OK	);		}		return 9;								// error code for initializing input system	}	GLe_InputOK = true;							// inputsystem available	return 0;									// error code if no errors}int COGLWnd::KillGLWnd()				{	if (GLe_Fullscr)							// check if we are in fullscreen mode	{		ChangeDisplaySettings(NULL,0);			// go back to previous mode, i.e. desktop		ShowCursor(TRUE);						// show the cursor again	}	if (GLe_hRC)								// check if we have a RC	{		if ((!wglMakeCurrent(NULL, NULL)) && GLe_ErrorMsg)				{										// try to release the RC			MessageBox(	NULL, "Error releasing the Rendering Context.",						"Error destroying the window!",						MB_OK | MB_ICONEXCLAMATION	);															// pop up error message		}		if ((!wglDeleteContext(GLe_hRC)) && GLe_ErrorMsg)					{										// try to delete the RC			MessageBox(	NULL, "Error deleting the Rendering Context.",						"Error destroying the window!",						MB_OK | MB_ICONEXCLAMATION	);															// pop up error message		}		GLe_hRC = NULL;							// delete the RC	}	if (GLe_hDC && !ReleaseDC(GLe_hWnd,GLe_hDC) && GLe_ErrorMsg)				{											// try to release DC if one		MessageBox(	NULL, "Error releasing Device Context.",					"Error destroying the window!",					MB_OK | MB_ICONEXCLAMATION	);																// pop up error message		GLe_hDC = NULL;							// delete DC	}	if (GLe_hWnd && !DestroyWindow(GLe_hWnd) && GLe_ErrorMsg)				{											// destroy hWnd if one		MessageBox(	NULL, "Error releasing the window handle.",					"Error destroying the window!",					MB_OK  | MB_ICONEXCLAMATION	);																// pop up error message		GLe_hWnd = NULL;						// delete window handle	}	if (!UnregisterClass(GLe_WndClass,GLe_hInstance) && GLe_ErrorMsg)		{											// try to unregister class		MessageBox(	NULL, "Error unregistering window class.",					"Error destroying window!",					MB_OK | MB_ICONEXCLAMATION	);																// pop up error message		GLe_hInstance = NULL;					// delete application instance	}	if (GLe_InputOK)							// if inputsystem availble	{		if (!InputSys->ShutDown())		{										// try to shut down input system			if (GLe_ErrorMsg)			{									// pop up error message				MessageBox(	NULL,"Error shutting down input system",							"Error calling InputSys->ShutDown !",							MB_ICONEXCLAMATION | MB_OK	);			}			return 10;							// error code for input system shutdown		}		delete InputSys;						// destroy InputSys object		GLe_InputOK = false;					// Inputsystem no longer available		}	return 0;									// Error code if no errors}  

I have the latest drivers for my videocard. If you need any more code, just tell me but I try not to post too much unnecessary code. thnx!