First off, you did not mention which "h", "P", or "Z" MB you are considering?
A motherboard is the single most important thing you have in a PC...............that's why it's called the Motherboard..........but yes, you can buy a cheap one if you like if it is compatable with the CPU....(socket 1155 for that cpu)......and speaking of the CPU, just a 2500 and not the "k" version, only $10 more in most cases and you get to OC the 2500k if you have the "P" or "Z"
"H"67 are not freindly to OC'ing
"P"67 are good for OC'ing but not so good for OC'ing GPU
"Z"68 are good for OC'ing both CPU and GPU
650W 80+ certified brand name is recommended for todays gaming PC's...MINIMUM.......yes I know you could get buy on a 500W but that will decrease as time will wear it out some..........and for the next GPU upgrades you will need something more
If you do not plan on gaming then any new inexpensive GPU will work for keeping the graphics loading...........can't see why you would consider that with all the nice stuff you are building
And if you are NOT going to OC or GAME or use two GPU's, then you can go with the 2500 and the "H" MB and a cheaper GPU (you would save a few dollars)