A lot depends on your motherboard. If you have the manual, it will tell you what the highest level processor it is capable of supporting. If you don't have the manual, find out the maker of the motherboard and the model number, then go to their website for this information.
You will hve to change the jumper settings on the board to get it to support a different flavour of processor, so make sure you note what the proper jumper settings are before proceeding.
Hope this is of some help.
boru