Given that Vista has been written, DES encrypted internatlly for signed approved drivers and hardware with very tight limits on anything that appears to be 'not normal', down to checking data streams every 30 milliseconds, I truly have to wonder if SolidWorks on a Vista PC is going to take a big speed hit? If you read the following article, you will get a flavor of just how restrictive and punishing the Microsoft requirements are on PC makers and software application engineers, and how that might translate into degraded or non-operating functions on PCs. [URL]http://www.cs.auckland.ac.nz/~pgut001/pubs/vista_cost.txt[/URL] Vista is for the biggy audio-video mega-corporation's benefits, and definately not for the technical user. For me, give me VISTA without the opportunity to run Blue-Ray & HighRes DVD super-duper stuff and audio codecs, and let me run SolidWorks on a FAST MACHINE THAT DOESN'T CRASH. Bo