Well, I have the same sort of setup that Krissta has. I run my poser on a Win2K box. I get the memory bug once in a while, but I know when it's going to happen, because I overload the scene, and have 'rosity, Photoshop, and ESPN open at the same time. As far as fragmentation, I just did a defrag 2 days ago. This is after weeks of playing with P6, but it was an absolute mess. Regardless of OS, if you are using Poser more than once a week, defrag often! My experience with Poser has been significantly better on Win2K than XP. I love Win2K, but XP has frequently given me a headache. Keep in mind, Win2K was built from the start as a server-ready enviorment. The server install could only be done once 2kPro was already on. That alone gives you better memory performance than XP, which was designed as a workstation-level OS. Granted, Win2k will be unsupported first, but that is what, 5 years from now? By then, you will have Poser 8, running on Win2K10, with a 100Ghz 128-bit CPU.