Need input on new rig [1500$] [First build]

I am planning on building a new rig soon, but need second opinions on several parts. This is what I am currently thinking of:

HAF X

EVGA GTX 580

Corsair TX950

EVGA Motherboard

i5 2500k

Hyper 212+

And OEM Windows, Arctic Silver, and a few other things.

Approximate Purchase Date: This month

Budget Range: 1500$, but can go a bit over

System Usage from Most to Least Important: Almost entirely gaming, but a bit of HD movies.

Parts Not Required: Keyboard, mouse, monitor, speakers, soundcard, HDD, DVD drive, and mabye RAM, seeing as I already have 8GB of it.

Preferred Website(s) for Parts: Newegg.

Country of Origin: United States

Parts Preferences: Intel SB, any mobo (Z68 worth it or P67?), full tower for sure, Nvidia vs AMD dosent matter, I'm open to either one.

Overclocking: Yes, I'm wanting to take a 2500k and push it to 4.2 to 4.5 GHz.

SLI or Crossfire: Mabye, but I'm only using one monitor, so it may be overkill

Monitor Resolution: 1920x1200

Additional Comments: I'm nearly set, I just need help on deciding between mobos, a GPU, and mabye a PSU. Besides that I want a high-end computer that will be upgradable, and prefreably quiet, but I've put up with loud, hot computers before, so thats no big deal.