mystery metal block


New Member
Jun 14, 2013
P6130002.jpgThis is my first post so forgive me for asking what might be a stupid question!! Fitted a new power supply and had the pc on its side with both covers off. After putting it all back together, found a quite heavy piece of metal on the floor.... 80mm long 40 mm wide and 10mm thick. It has a recess in it carying in depth from3mm at one end to 8 mm at the other, Did this fall out? If so, what is it or did the cat bring it in?!!! Many thanks