yes,
thanks for help.

i already know i could reduce texture size...but no, i can't because, i'm doing some closeup viewpoint in the animation like this one :
http://www.frenchcinema4d.fr/hub.php?doc=image&image=4986

so, to have a perfect zoom on her eye, i need a big texture...

i really wonder why poser don't use more of my memory !
my render is not finished yet (after 12hours), and only 300MB of memory are used !!!!