We recommend buying UiO "standard models" from Dell, Hewlett Packard or Lenovo. They give well-balanced systems that are easy to maintain, and the pricing for UiO is especially low on them. jon.tolgensbakk@geo.uio.no handles all computer-system orders and can get you the specifications for the UiO models.
If you would like to browse the models feel free to do so. At present (September 2007) Latitude D420/D430, D630 and D830 are available as UiO laptop models and Optiplex 745 is the UiO desktop model. The Hewlett Packard laptop models are HP 2510p, HP 6910p and the HP 8510p. The desktop model from Hewlett Packard is the dc5750. At the moment T60p and X60 from Lenovo are also supported. All options might not be available as UiO models, and the pricing will be different as well.