Well for one thing it crashes all the time(something that doesn't happen with XP or 7),it seemed to have real problems with certain video cards, it had a huge amount of trouble running older programs and games, it was give me error messages all the time and some times they would up just when i turned on the computer and my laptop came with Vista preinstaled, It had real trouble writing anything to a disc in a way that would work, then many times it would just refuse to read anything I plugged into the USB ports. All of these problems vanished once I replaced Vista with Xp and not a one of them has turned up on Windows 7. Vista was a nightmare I never want to return to.