There is no doubt that you need to upgrade your psu. The chances of the psu going loco with that videocard are around 90%, don't bother taking any risk on that. You need a new psu that can atleast handle 400w or up (you might not need it all but just in case)
Uatx mobo's are not that special and should be able to handle most basic cpu's or if you want a really good one:
A Zalman!
Good luck :thumbup: