IMHO, Windows 2000 works better with Poser (I teeter back and forth between XP and 2k), especially 5. I also have a Hyperthreading CPU and kuroyume is right, Poser doesn't take advantage of it regardless. To be quite honest about it, the HT technology at this point seems a bit overhyped. I don't find much of a multitasking improvement -in general- installing an OS with it on.

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