You don't need to upgrade your powersupply. It's fine for this build. Only need to upgrade if you add a second video card.
Overkill is relative. what you have there seems ok to me. But the HDD seems expensive. Personally for $100, I'd be going for an SSD. Even a $130 256GB Agility 4 is going to run rings around that hard drive... Case is pricey to me but that's subjective- if you want it, go for it.
It depends on your uses, that CPU is way overkill for simply gaming, for lots of rendering and editing, it is quality. May not be worth spending so much on a CPU now though, this is the last gen in the 1155 socket.
It would help if you said what you intend to do with this PC. Either way, the motherboard is probably overkill. If all you want to do is game, the cpu is overkill too. A 3570k is good for most uses. I would also include an SSD (your second link in storage didn't work) and would go with a Samsung 840Pro or Crucial M4.
I guess if I were to go with the 3570k I could also save some money and go for a different motherboard.
I've been browsing for cheaper HDD but wasn't really able to find any with solid reviews for less (I'm sure it's out there so I'll keep looking). The reason I went with a 500GB was because of my intent on also getting a SSD.
It won't overheat at stock, it's just that it is not the greatest OC'er, gets pretty hot at higher clocks. No HDD's really have great reviews on Newegg, those with issues are more likely to post complaints than those who were satisfied. Caviar black is quite reliable and has a 5 year warranty, I believe Toshiba makes another highly rated drive.
If thats a new-gen SSD, it's a pretty good deal, otherwise keep an eye out for Samsung 830 or something, I got a 128gb for 70 bucks and that is only a 1-gen old SSD.
If you've been reading the threads here you’ll get the drift real fast. The first thing you need to do before you assemble your build is to put the CPU/Cooler in the MB along with a stick of Ram and the GPU. Power them up and see if you can get to BIOS. I call this the smoke check.
Second is to inspect the case thoroughly and to remove any burrs or dull any sharp edges that could abrade a cable or ground out a motherboard.
Take your time on the build. If you do everything right you won’t need to go back in there for awhile so take your time and do it right. Cable management is not just for a pretty case, it helps airflow and that helps keep everything cool.
Consider a closed loop liquid CPU cooler.
Good luck and come back if you have any issues. Some of these guys are pretty sharp.
I have the Asus P8z77-V Pro, it is slightly lower specced but not much, and is cheaper, it has all the features you would need in a gaming rig (plus an included wireless card/module), I believe if you drop down another model or two the wireless is not included so it becomes slightly cheaper. The P8z77-V Pro is a very quality board IMO.