I made a few pictures of em. hope that helps to pinpoint it down.
and thnx for the answers so far.
There are normally a set of little etched markings in the top of the heatspreader that give the clock speed, cache size, bus speed, and the model ID (S-spec, such as SLACR or SL82V..) You would need to get some solvent like 91% isopropyl alcohol or toluene to remove the thermal compound to see that/
I am about 99% sure that it is a 3.20 GHz Xeon 5060 "Dempsey," judging by the pen markings ("Dem 3.20") on the chip. It is the Xeon equivalent of the Pentium D 940 and is a few years old, which would make sense as to why they are giving it away.