Open a terminal from Applications/Accessories and then type wine regedit - you will get a registry editor like in WIndows. If you are not familiar with it, you can do: - open the tree until you have wine selected; - then right click and select New->Key (not so logical since you are making a folder, but it works) - then right click on Direct3D, and choose New->String, and type VideoMemorySize - finally right-click on entry you just created, and put your video memory size, which you can find with, e.g. nvidia X Server settings in menu System/Administration
