i use a microatx board with my core 2 duo.
got it during the $20 off $50 buy.com google thing.... for $70 shipped...
its an intel branded d946gzis. its very stable, was cheap, and best of all unlike the 965 boards... it can actually run most linux distros out of box, doesnt have any problem with IDE devices because it has a real IDE controller in the ich7 etc. the 946gz chipset also manages to use about 20 watts less power than a g965 when idle. i guess the g965 is pretty power hungry.
i would assume the p965 vs p946 would be about the same.
2 main drawbacks of it are... only 2 ram slots, and not overclocking , neither of which are much of a concern for me.. but could be for you.