The item link you provided didn't return a product when I clicked it, but you have to get a motherboard with the same CPU socket type as the CPU you're going to get. There's no assurance of compatibility otherwise, I'm guessing that was an erroneous product description, which is why the link is dead now (at least at the time of my post).
I pretty much agree with myuusmeow on the points about PSU, every enthusiast will try to tell you to get more than you'll use, and if you do that then you may not wind up investing the cash in a good brand of PSU. I've had good experience with Antec PSU's.. though I do run with a 750w in my tower because I had planned to use more drives than I wound up with in addition to not ever wanting to have to replace it in the case I have, and wanting the ability to power a Crossfire (double video card) setup if I wanted in the future. All of which are enthusiast concerns. Don't spend extra on a 750w (or higher..) if you this is your first "from scratch" custom build.
From what I understand/been told, PSU's wattage draw regardless of internal device usage. The PSU's job is to have that power continuously available. If you're running a 600w that's what its going to pull from your outlet when it is on.
edit: I forgot to discuss specific.. information I wanted to mention to help you select a video card. There's four very important criteria in selecting a video card for 3d gaming, aside from brand and the price range. But I don't wanna copypasta all I said on the Ask GBAtemp question about budget graphics. I was actually fully awake when I wrote that so the details are all
there if you want more.
I don't know what budget you're trying for, or what generation of games you'll be trying to play, but the choice on which card to get will depend heavily on your budget and your performance goals. If you're building a budget rig primarily for gaming, then it's likely that it will be worth allowing the video card to be the most expensive component. If you want to do moderately recent 3D games at good* framerates in 1920x1080 or 1650x1080 res, then you will have to spend over a hundred bucks.
I'm passing out now, awake over 24 hrs straight is rough with no caffiene supply