Does my mobo support a celeron D?

Solution
The chipset supports 533 fsb cpus, so probably yes. But I won't guarantee it. As with most oem boards, you upgrade the cpu at your own risk, unless a cpu support list is provided by gateway, hp, etc.
An oem board is manufacturered specifically for a manufacturer of computer systems like dell. It won't be listed on the board manufacturer's website, but on dell's website. The only oem boards that I've seen with cpu upgrades listed were on compaq's website.