Slightly over budget but a stonking deal...

http://svp.co.uk/product/dell_inspiron_6400_with_3_minus_year_warranty_plus_windows

If you e-mail Steve at SVP (no connection to me, just found the deal elsewhere) mentioning the 'DVD forums', he'll send you a code to enable you to get it for £450 delivered. More than £100 less than getting it from Dell Direct.