So I bought a Dell Inspiron 531 in November of 07 and it came with Vista. Which was alright but it seemed a little sluggish with some games and apps I ran. I could not get FSX to run smoothly at all. So the other day I said screw it! I asked my girlfriend for her XP cd. Booted off the CD deleted the whole hard drive, formatted and installed! Went beautifully minus a few bugs. XP wouldn't recognize the network card, usb, sound or video drivers. So I just went to Dell.com and downloaded the XP version of those drivers and burned them on a dvd and installed them on the desktop. Best "upgrade" I've ever done. The computer is so so so much faster and FSX is silky smooth with all the settings turned up.