loose screw holder on motherboard

I have an Dell XPS 1530 and it wasn't turning on. Upon investigation it seems that the screw holder that holds the heatsink and fan in has come off the motherboard and is not allowing the heatsink to sit properly on the processor. Does anyone know how to put this holder back onto the motherboard? It was attached to the screw so I was able to get it, but I can't seem to get it to fit back into the motherboard. I am afraid to push to hard in worries of breaking the motherboard. Help please...