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Important note about Windows 7 and 8

There is currently a known issue with Windows 7 switching between resolutions, which is caused by a bug in Windows 7 / DirectX.

If the desktop is running at an interlaced resolution (eg 640 x 480 on a standard-res monitor), When any game which uses a non-interlaced res is started (which is pretty much any Mame game), an error resuts "Unable to initialize directdraw".

Note this only happens if the desktop is running at an interlaced res, which is the case when using a standard res monitor (not a multi-frequency monitor).

There is a workaround for this: Run the desktop at a non-interlaced res such as 640 x 288. This might mean using a front end which has a 640 x 288 mode such as Mamewah.
The resolution can be switched using the Quickres icon.

There are also 3 useful utilities which can be downloaded here. These are simple programs which change to the specified res. So, you can configure a front end to run 640x288.exe to change to this resolution before starting the game. Once this has happened, Mame will then be able to invoke the correct resolution for the game.

Note to Mame devs: This issue does not arise if D3D is selected. But owing to not being able to disable stretching in D3D in Mame this results in a poor quality picture.