My system:
Core 2 Quad Q6600
Geforce 8800 GTS 512MB
4GB Ram
Windows 7 x64 Pro

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From default.c :



(memory)

- nx = nexus = i.e. file cache used by the current level.

- m = sys_memory = Virtual memory currently allocated by the engine for nexus, level, entities, and engine objects.

- geo = level textures

- shd = d3d_texsmaps = Amount of video memory currently used for wmb shadow maps. Adding the d3d_tex.. variables gives the total sum of video memory currently used for the game. Due to swapping and compression, the total value can be remarkably higher than the amount of video memory available on the 3D card.

- ent = d3d_texskins = Amount of video memory currently used for level models. Adding the d3d_tex.. variables gives the total sum of video memory currently used for the game. Due to swapping and compression, the total value can be remarkably higher than the amount of video memory available on the 3D card.

- v = d3d_texfree = Indicates the amount of texture memory still available on the 3D card, in MB . Is also displayed in the statistics panel. Can be inaccurate, depending on the 3D card driver. The real amount available for 3D textures is less than the memory on the 3D card, due to screen and other buffers. The video memory normally available at game start is can be several 1000 MB on new 3D cards, but 30 MB or less on old cards (TNT2).