This is still a problem with P5. I'm not running scenes with hair and so far I've never even tried to render a scene that needed virtual memory. Nevertheless, I still get this problem when memory usage gets high. Currently I'm using XP which is based on the Windows NT kernel, and while Micr$oft OS's may be an easy scapegoat when anything goes wrong, the NT kernel is mature and well known to be rock solid in memory use. Using virtual memory (disk) rather than physical RAM should be transparent to any well written application under NT, the only effect being a slowdown in performance. This is patently not the case in P5. Hopefully feedback from the debugging code will allow CL to identify the problem code and fix in in the next patch. Bill