If you don't have the board, one way is look at the other boards on Zalman's compatible list. Very few boards if any have a "one of a kind" design/layout. So there are bound to be other boards with the same layout as the P5WD2. For example, looking on Zalman's list, the P5GD2 is compatible. Looking at pics of the P5GD2 and P5WD2 they are the same layout, at least as far as the surrounding socket area. If one board is compatible and another board has the same layout, logic would lean toward the 2nd board also being compatible.(1) No motherboard components with a height greater than 39mm (1.53inch), as well as the PSU, disk drives, VGA card, and RAM should be present within a 68mm (2.68inch) radius from the center of the CPU.
(2) Distance between the side of socket 775 and the PSU must be at least 44mm.