then switching out a power supply should be no different. (get one that's a little larger, and recommended by arstechnica -- saggy power sucks (ask yer pap if you don't know what that means, teehee)). Just remember which went where (write 'em down if you have to), and plug them back in.

It really is simple.

And if you order from newegg, it's fairly easy to send back if you get the wrong one (I too heart newegg).