anchor.diff:      intel        = { modules = [ xorg.xf86videointel ]; };
       nv           = { modules = [ xorg.xf86videonv ]; };
       nvidia       = { modules = [ kernelPackages.nvidia_x11 ]; };
  -    nvidiaLegacy = { modules = [ kernelPackages.nvidia_x11_legacy ]; name = "nvidia"; };
  +    nvidiaLegacy = { modules = [ kernelPackages.nvidia_x11_legacy ]; driverName = "nvidia"; };
       openchrome   = { modules = [ xorg.xf86videoopenchrome ]; };
       sis          = { modules = [ xorg.xf86videosis ]; };
       unichrome    = { modules = [ pkgs.xorgVideoUnichrome ]; };
       vesa         = { modules = [ xorg.xf86videovesa ]; };
  -    virtualbox   = { modules = [ kernelPackages.virtualboxGuestAdditions ]; name = "vboxvideo"; };
  +    virtualbox   = { modules = [ kernelPackages.virtualboxGuestAdditions ]; driverName = "vboxvideo"; };
       vmware       = { modules = [ xorg.xf86videovmware ]; };
     };
   
  
positive.code:         
            Section "Device"
              Identifier "Device-${driver.name}[0]"
              Driver "${driver.name}"
              ${optionalString (driver.name == "nvidiaLegacy") ''
                # This option allows suspending with a nvidiaLegacy card
                Option "NvAGP" "1"
  
negative.code:     optional (cfg.videoDriver != null) cfg.videoDriver ++ cfg.videoDrivers;
  
    drivers = flip map driverNames
      (name: { inherit name; driverName = name; } //
        attrByPath [name] (throw "unknown video driver `${name}'") knownVideoDrivers);
  
  
  