The U1E however has an advantage over the U1F, as it includes features such as a pre-installed copy of Windows Vista (as opposed to the U1F, which uses Windows XP) and a larger amount of RAM (1.5GB as opposed to 512MB). The pre-installed copy of Windows Vista Business makes the laptop compatible with a large amount of software that older operating systems cannot use. This lets the user keep up to date, and lets them access newer programs, and many programs that have yet to be released. The 1.5GB of DDR2 RAM lets the user the user run many programs at once, and smoothly. It also gives them full compatibility with programs that require a large amount of system resources.