It's not at all a stupid question.
Depends on whether it's an original SECC processor or the newer SECC2.
The SECC mount had locking tabs at the outside top corners of the frame.
(The tabs are sort of T shaped, if memory serves.)
SECC2 uses clips that capture notches in the ends (sides) of the metal
frame of the SECC2 cartridge itself. I generally released them by
careful use of a flat-bladed screwdriver, which I inserted between the
frame and the clip. (See the Intel document linked by another poster. I
doubt that you wish to remove a retail Intel SECC2 heatsink, but the
pictures in the .pdf will show the notches etc.) It's roughly the same
level of difficulty as removing a retail Intel P4 heatsink, although
maybe less obvious.
If someone glued an SECC2 processor into an SECC slot (to avoid
replacing the retention brackets), that would make removal a bit harder.
Good luck.
Bob Knowlden
Address may be altered to avoid spam. Replace nkbob with bobkn.