1. The CPU is great
The K-Series from Intel generally are really good processors for gaming.
2.The PSU you can always just get a CX500 if it is cheaper (I use a GTX770 and it still works fine
)
3.HDD is Good, is it 7200RPM? And also you may want to consider SSD storage for a faster operating system and Games. Only download programmes on it though and use the 1TB as a dump drive
, Heres a Link to one.
http://uk.pcpartpicker.com/part/kingston-internal-hard-drive-sv300s37a120g .
4.GPU I may be a bit bias on. I prefer Nvidia because they tend to work better with Intels. If you were to get the competitor of the RX 270x I would get the GTX760 or wait for the GTX 860 to come out.
5.RAM is fine, althought you only really need 1600MHzz, speed actually dosent really matter when it comes to gaming its just a way to leech peoples money.
6.For the motherboard all you really need is a new chipset and for it to support the 4th gen series.
1. You need an OS, I would reccomend Windows8 or 8.1 and then installing start8 to get the windows 7 bar, heres a link : http://www.stardock.com/products/start8/ (Idk if 8.1 has that already though, search it
)
2. For a case I would reccoment a Bitfenix comrade or a Corsair Carbide 300r.
3. For a disk drive get a cheap and cheerful samsung one that is like 12 Euros.
4. If you would like to overclock I would reccomend getting a Refurb of an h80i as they are sooooo cheap and thy are nearly new. I got a Refurb of a h100i and it is a charm.
You have a decent build, but I hope I helped :3