Well, you know that... it's impossible to say why it's slow with the info you are giving don't ya?. Processor model and speed, distribution, amount of swap, graphical interface you are using (gnome, kde...) graphics card (it may influence immensely into your graphic-speed performance), what applications are you trying to run that are slow? (OpenOffice is extremely slow even in a 2ghz). Well, you got the idea