Cruez, good question. If your mobo will support that P-3 600, you can test all of them on it.
The difference is in the packaging, and this pretty much affects only heatsink/fan you can put on each of them. The holes in the processor card and casing are in different places, so an HSF for one type won't work on the other.
Your P-3 is definitely an SECC2, the others are almost certainly SECC's.
So yeah, they'll both work in the same mobo, if the mobo will support that P-3