haha, I just finished testing my new machine and was thinking of creating yet another of these threads.

I guess everyone upgrades at this time of the year.
Anyway, pretty much any 939 motherboard will support X2s with an appropriate BIOS. What exactly are you looking for in a motherboard?
As for power supplies, don't get that first one you posted, but the other one is pretty good. Although I would suggest
this or
this instead, which are server class PSUs for great prices. If you want something a bit nicer looking with similar power,
this is also good but they seem to have jacked up the price in the last few days.