Mechanical issues, bad boards. Costly to fix if you can't take care of the mechanical issue your self. If I saw it I might peg the repairs at about 600 to include a new main board and some plastic housing parts.
I've just boughgt old Toshiba Portege M400, but it is faulty. When I take it to my hands or touch it in the place around HD it collapses (black screen, fan is running on high speed) or freezes. I've removed the hard disk and it seems it is not collapsing any more. When the hard disk is inside and I do not touch the laptop then it is working without problems. Any clue what can be the problem and which tests to make?