I'd say, move on. I have tried running Wildfire on a P4 3.0 GHz desktop and on a P4 2.66 GHz laptop (1GB RAM on a desktop, 512 MB - on a laptop), and in both cases it is much slower, very noticeably so, than 2001. However, it is workable on both. So my advice would be a P4, 2.8GHz or higher (800MHz front side bus version), 512MB RAM or more, and a video card with at least 128MB of dedicated video RAM (preferably NVIDIA, QUADRO if possible). As far as OS, I'd go with XP. As far as I know, Pro/E is not supported under NT anymore (certainly not under NT 3.5, and even if they have not yet discontinued support for 4.0, they soon will), so on a Windows platform you are choosing between W2000 and XP. In my opinion, XP is easier to use, configure and tweak, as well as more stable (at least after all the latest patches have been applied...:). It is also somewhat slower than W2000, but not by a lot. Since, I am afraid, MAC OS X support is out of question for the near future, the only other alternative you have is LINUX. Unless, of course, you have the $$$$$ for an SGI machine...