Dell technical support.
Found out why my lappy was behaving like an arthritic 486 after 15 pints and an eigth of red-seal despite a format and come again... CPU fan is fuckered making the CPU burn like Michael Jackson at a CocaCola commercial.
Despite being 2.5 years old Dell are sending a technician round with a new mobo, cpu fan, system fan and since it got so hot, bottom of laptop plastic thingy. They are also sending me a new hard-drive just in case the old one got damaged by the heat.