Video Device Driver Entries

This section describes the entries for video device drivers under the DeviceMap subkey and under the CurrentControlSet\Services subkeys for specific video drivers.

Video Driver Entries in the Services Subkey

The following values, which can be set in a video driver subkey, affect system performance.

DefaultSettings.BitsPerPel REG_DWORD Number of bits per pixel

Contains the number of colors for the mode requested by the user. For example, for the v7vram miniport, the following value yields a 256-color mode:

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   DefaultSettings.BitsPerPel = 8

DefaultSettings.Interlaced REG_DWORD 0 or 1

Determines whether the mode requested by the user is interlaced. For example, for the v7vram miniport:

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   DefaultSettings.Interlaced = 0x0 (FALSE)

DefaultSettings.VRefresh REG_DWORD Number Hz

Contains the refresh rate of the mode requested by the user. For example, for the et4000 miniport:

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   DefaultSettings.VRefresh = 72

DefaultSettings.XResolution REG_DWORD Number of pixels

Contains the width of the mode requested by the user. For example, for the et4000 miniport:

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   DefaultSettings.Xresolution = 1024

DefaultSettings.YResolution REG_DWORD Number of pixels

Contains the height of the mode requested by the user. For example, for the et4000 miniport:

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   DefaultSettings.Yresolution = 768

Video Driver Entries in the Software Subkey

The optional entries for open graphics libraries (OpenGL) are under the following subkey:

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HKEY_LOCAL_MACHINE\Software\Microsoft\WindowsNT
    \CurrentVersion\OpenGLDrivers

%display_driver_name% REG_SZ %OpenGL_client_driver_name%

For example, suppose that MYOPENGL.DLL is the OpenGL client driver for the display driver MYDISP.DLL. Then the OpenGLDrivers subkey would have the value-data pair:

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   mydisp: REG_SZ: myopengl

The subkey may be empty if no OpenGL client drivers are installed. This value can be changed via the Control Panel Display option. Manual modification should not be necessary except for manual installation or uninstallation of OpenGL client drivers (which is different from the OpenGL built into the GDI). Only one client driver is allowed for each unique display driver name.