It's probably on an i810 or i815 motherboard with intel onboard graphics *shudder*, upgrading to a fast Tualatin core can be problematic, dependant on chipset revision. Also they do need a bit of ventilation so a tight case might not be ideal to upgrade past a 1Ghz chip. Strange format cases also give you headaches when you want something as simple as another NIC or graphics card. 256MB ram would be fine with a lightweight OS though. Default install of XP on 256MB only has about 64MB free RAM left for user programs after boot.
