Dells should be able to run AutoCAD flawlessly. My old high school (i graduated in june, so i get to say that now :P), ran AutoCAD software on Dell desktops for computer courses, like Computer Design and Architecture Design, and there was no delay. I don't remember what year AutoCAD it was, I had both of the aformentioned courses in my Junior year, which was right after the school bought mass Dell desktops. Now bear in mind, these are school computers... High School Computers... Public High School Computers... so they are by no means top-of-the-line, just P4, XP Home, and a small amount of memory. That's about it. Hope that helps.
2002 Chrysler 300M Special, DSB | 2007 Dodge Charger R/T Road & Track, BB
2000 Dodge Intrepid SE - Champagne | 2001 Dodge Intrepid ES - Sapphire Blue Pearl | 2003 Pontiac Grand Prix Ivory