I'm running an Intel D5875PBZ for my motherboard.
I'm assuming you meant "D875PBZ", as I can find no info for a "D5875PBZ".
If so try here:http://www.intel.com/design/motherbd/bz/bz_proc.htm#Note
Make sure your board is at these revisions:
C27085-207 or later
C26680-206 or later.
The bottom of the page shows where to find the board revision info.
If your board isn't at these revisions, a Prescott isn't going to work.