mikeb2817,
Yes,
CPUID (CPU-Z) is a MUST-HAVE utility.
And aside from what Windows' own "System Information" can tell you, two other neat (and free) utilities to have are
Belarc Advisor and
Speccy:
http://www.belarc.com/free_download.html
http://www.piriform.com/speccy
Have not used Speccy myself (but that guy Bauer over @ Tiger Direct doing the How To Videos mentioned it) but have often used Belarc Advisor...especially when I am trying to help someone else with their hardware issues and they have NO IDEA what hardware (brand names, versions, nothing) they've got: I put Belarc on their PC and it comes up with all their hardware (including mobo info) AND installed software, which you can then print out if you wish for later reference.
Whatever, these are good to have for your OWN computer, let alone helping someone else (I have Belarc on my 2 PCs).
As for the OP's issue, hopefully
Asus will have that info on their website:
http://support.asus.com/download/model_list.aspx?product=1&SLanguage=en-us
...see if your "Deluxe" model is the same or very close to one of the other P2B mobos listed on the page above as far as what CPUs are supported (download their manuals maybe and find out how they compare/contrast to your "Deluxe"). But if the "P2B Deluxe" is nowhere to be found at Asus, put the motherboard's model # into a Google search and maybe there is a review on it, as those usually cite the mobo's specs, too. I've found info (and reviews) on some pretty old and long-obsolete hardware (like reviews on FLOPPY DRIVES), so the info has got to be out there somewhere.
Good luck...
P.S. It's not one of the 12 "P2B" models listed here?
http://support.asus.com/faq/asus-faq.aspx?SLanguage=en-us&no=2E219602-E58E-A2E6-B423-86B401BEF2A9
Maybe Asus doesn't use the word "Deluxe" but just the model # only. Use one of the info utilities to find out the exact model # (or open up your PC and read it off your mobo if the model # is printed on it).