AGP Aperture Size
Possible values of an option:
[256MB], [128MB], [64MB], [32MB], it is possible [16MB], [8MB] and [4MB]
The option description:
The maximum size of a random access memory which can be used for storage of textures by the videocard with interface AGP or PCI Express. As a rule, optimal there is a selection for this purpose from  (for AGP) to  or  (for PCI Express) Mb.
Selection of 64 Mb does not mean that 64 Mb of physical storage will be permanently occupied. Selection only logical addresses Means, physical storage is requested only in case of real necessity for it.
Other options identical to destination: