£600-£700 Gaming Build Help

So as the title suggest I'm a first time pc builder and planning on building a new gaming rig/general workstation build. I have been looking at building one for some time and recently my 5year old Desktop finally packed it in last week. Now that's forced my hand a little so I'm taking the plunge and building one.

my is Budget £600-700 I'm from the UK, the cheaper the better since I plan on buying windows full retail which is about £130 but will add a little extra for that, my preference is buying from amazon but will go somewhere else if needed.

current build idea:
http://uk.pcpartpicker.com/p/25yXS
 
the case is not on pcpartpicker
http://www.amazon.co.uk/gp/product/B00CGWQ7D4/ref=ox_sc_act_title_1?ie=UTF8&psc=1&smid=A3P5ROKL5A1OLE
which is £28
 total roughly: £630

I have an optical drive and a HDD from my old pc which I will use.

I will eventually OC the CPU, but not straight away.
also is it worth changing the F6X 300 to the FX 8320 is it worth £30 more?

Games I play/ intend to play: Rome 2 Tw, BF4, metro last light, GW2 and crysis 3 ect.
I would like to play them at 50-60fps currently play at 1080p. and on high-ultra settings

any help and suggestions is much appreciated.
Thank you.

I would go for an FX-8320 so you don't have to buy a new CPU in a couple of years.

FX-8320 would be quite an improvement, especially in BF4.  I would recommend it, and your motherboard can easily support it.

Everything looks good.