Bear in mind that a Vicky3 pz3 file is much larger than a V2 one. I often attempt large scenes and almost choked my machine (P4 2.4Ghz, 1Gb RAM) on one of my recent renders. 6 Vickys, (3 of them Vicky3s) and the pz3 file weighed in at 479Mb. So an older system might cope with rendering a Vicky 3, but I doubt if you could put more than 1 in a scene. You'll save a bit on your system resources by using medium-res textures in place of hi-res as well. My experiences have shown that its the textures, not the geometry, that suck up your free RAM.

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