CPU falls out

[Jeremy]

Revisiting my CPU problems, I think I have discovered at least part of the problem
- the CPU comes loose in the socket.  The socket looks like a Socket 7 but isn't.
 It has wells for the pins that are much wider than the pins.  The procedure
to inset a chip appears to be:  Drop chip in, slide sideways (there are split
pins attached to one side of the wells the pins go into).  I have tried just
pushing down, this does not appear to connect the pins.

There appear to be none of the usual levers or whatever to lock the chip in
place.  I have been using a butterknife to lever the chip over, but it doesn't
quite do the job.  Evertime I go to bolt the heatsink on or turn the laptop
over the CPU comes loose.

Are there any hardware guys who can tell me the right way to go about this?