Not sure.
I checked the Intel site and the socket for the D 940 is listed as "PLGA775" whereas the one for your 630i is likely "LGA775".
Also, even if the sockets were completely compatible the motherboard manufacturer would need to have an entry in the BIOS for the board that detects and allows support.
*Thus, you would have to find the EXACT CPU support list (at motherboard support site if one exists).