i really dont see much room for losing that $50 to get the benq. i guess you should just bump your budget up to get it. other than that this is a solid build

There is no reason for you to get a single 8GB RAM dimm. Your motherboard supports 4, you should probably get 2x4GB, unless you plan on adding more later.
I'd suggest this or this

If you are on a tight budget, maybe dont do this, but I see that you dont have a ssd in there. That might be a possible upgrade along the road? And also you cold loose a few bucks of the ram if you looked around a bit, also you might loose like 10 bucks of that mobo.

Seriously this 2x4GB is A LOT better than 1x8GB, do to your ability to setup Dual Channel.

You also don't really need the anti-static wrist strap, just touch a piece of metal (like your case in most instances) before you touch electrical equipment.

-edit-

1 last thing, you can probably do without the Keyboard, getting a 120Hz > Decent Keyboard.

At a quick glance I would be dropping that keyboard, nothing special about it compare to a $10 keyboard.

PCPartPicker part list / Price breakdown by merchant / Benchmarks

CPU: Intel Core i5-4670K 3.4GHz Quad-Core Processor (£188.39 @ Aria PC)
Motherboard: ASRock Z87 Extreme3 ATX LGA1150 Motherboard (£125.46 @ Ebuyer)
Storage: Seagate Barracuda 500GB 3.5" 7200RPM Internal Hard Drive (£37.19 @ Aria PC)
Video Card: Gigabyte Radeon HD 7850 2GB Video Card (£154.03 @ CCL Computers)
Case: Xigmatek ASGARD PRO (Black) ATX Mid Tower Case (£36.49 @ CCL Computers)
Power Supply: SeaSonic 520W 80 PLUS Bronze Certified ATX12V / EPS12V Power Supply (£64.10 @ Amazon UK)
Keyboard: Logitech K120 Wired Standard Keyboard (£9.99 @ Amazon UK)
Mouse: Logitech G400 Wired Optical Mouse (£38.99 @ Amazon UK)
Other: BenQ XL2411T (£225.89)
Other: Crucial Ballistix Sport 8GB (2x4GB) 1600MHz (£49.99)
Total: £930.52
(Prices include shipping, taxes, and discounts when available.)
(Generated by PCPartPicker 2013-06-29 16:46 BST+0100)

7850 1 GB model to 2 GB (for even cheaper)
120 Hz monitor.
Single channel memory changed to dual channel.
A cheaper keyboard (which isn't bad, mine is still nice after 2 years of use), I don't see the reason to pay more if it's not mechanical.
520W should be fine for now, but in the long run I'd rather save up some more money and buy a PSU with more power then you could just upgrade your GPU and still be good to go.

Peripheral shenanigans aside you're essentially squezing a 4670K (emphasis on K) into 700£ PC. There is absolutely no point in doing that, this CPU is basically oversized for that budget. Without an aftermarket cooler you won't even see any benefits from the 4670K compared to the non-K because the best you could hope for is not getting thermal throttled as soon as turbo boost kicks in, not even wasting a thought about overclocking.

Even TF2's love for high per-core-performance doesn't justify your choice.

Drop the 4670K and go for a FX-6350 with a decent cooler and you still got enough money left to upgrade to a 7870, 1TB and a small SSD.

If you want the Intel/Haswell swag really bad and you are willing to sacrifice overclocking then go for a cheaper i5, something like the 4430 or the 4570.

Head over to http://www.logicalincrements.com/ for some basic suggestion or to
http://www.reddit.com/r/buildapcforme if you want some more in-depth complete build suggestions or to
http://www.reddit.com/r/buildapc for more specific tweaking on your current build idea.

As for the budget cooler later on get Hyper 212, it has great price/performance ratio.

Sorry, i must have skipped that line.
Nonetheless i still can't understand why you want the i5-4670K.
The 7850 will reach it's limit way before the i5-4670K.

When do you plan on buying the cooler?
And when do think you'll max out the 7850? Like zilis said you'd need another PSU aswell is you upgrade the GPU.

Sorry, I just realised I made a mistake in the original post, I forgot to mention that the GPU I was planning on getting was actually a placeholder (It's not listed on PC partpicker) for This, an XFX version of the card with more ram+higher clock.

Edit:I made a similar post on a hardware forum and they recommended I change the GPU as well, I'll look into that

TF2 being a CPU limited game I would see it perfectly reasonable to shoot for a 4670K and wanting to overclock it with just a 7850. Not to mention a better CPU is more helpful for Streaming/Video Editing.

Having cpu overhead isn't necessarily a bad thing. Overclocking is kinda a hobby for some people, and plus it gives you a platform to move on from. This motherboard/cpu combo could last him quite a while; it's pcie-3 with no pcie-4 in sight, it can hold up to 32gb of ram, has a good amount of usb3 ports/headers, and with a good cooler and a decent overclock that cpu will be competitive with the best for a long time. A generation or two from now, when the 7850 is showing its age, he can upgrade to a new mid-to-upper end graphics card which will probably be faster and still fit the same power requirements by just unplugging the old one and dropping the new one in.

Basically, if he /really/ needed some better graphics now, I'd say you're right, get a worse cpu and spend that on a better gpu, but I think this system as is will be worth more in the long run.

Also I have an xfx card with the same cooler, they're nice. Easily one of the quietest graphics cards I've been around, even under load.

as far as what ppl are saying regarding dual channel memory having an advantage over single channel is pretty much only a very slight advantage, i see nothing wrong with going 1x8gb which would allow you to get 16gb on 2 sticks, and still (albeit the practicality isn't realistic at this time) have the option to move to 32gb someday

I've been recommended either This:http://uk.pcpartpicker.com/part/sapphire-video-card-112001420g
Or this:http://uk.pcpartpicker.com/part/evga-video-card-02gp42660kr
To replace the GPU. I'm thinking of getting the GTX 660, thoughts?

Overclocking is like the lottery, not all K chips are created equal. Some might be able to get to 4.6GHz at 1.200V while others need to push 1.400V (which make the chip much hotter).

Please check the temperatures of the Haswell chips because they don't overclock well due to high heat output. Unless you are planning on dropping around $100+ on an aftermarket cooler you might not reach acceptable temperatures on the the i5-4670K with a high clock like 4.2GHz+.

Every generation of intel CPUs seems to be getting worst at overclocking. The 2500k Sandy overclocked better than the 3570K ivys with lower temps, and the same with haswell vs ivy. A lot of overclockers are disappointed with hawsell and I personally went with the 3570K after seeing hawsell results.

If somehow you are lucky enough to get a good haswell chip without overheating, they do perform 10%~20% better than ivys.

#14
It really depends on his budget now and in the future. Getting a 1TB HDD and a 600+ Watt PSU would probably save him some money.
I was assuming that he doesn't need the power of an overclocked 4670K right now because he wants to buy the cooler later. That means that he could buy a cheaper CPU now and then buy a overclockable broadwell CPU later so he could keep the mobo even longer.

EDIT: #16
I'd say go for the 660

#17
Pretty much this. To get more out of Haswell than Ivy Bridge if you overclock you pretty much have to do at least two of these three things:
- get a really good cooler
- be really lucky with the CPU in terms of overclockability
- delid it

Plus the LGA1150 will be kept for Broadwell so a non-K Haswell and an upgrade to broadwell later might be better.

I still don't know when OP wants to buy a cooler but with the stock cooler the 4670K might have some problems using turbo boost due to the temperatures.

If you want to overclock the 7850 it will destroy the 660. In recent generations AMD has really been kicking GTX's ass interms of performance and price because of its ability to OCed much better. Around the same price point I would suggest AMD GPUs over GTX cards. However, the only thing GTX has over AMD is lightboost, which almost gets rid of input lag on 3d monitors.

#19
Lightboost should be a lot more noticable than the better performance of the oc'd 7850. Why go 120Hz and then miss out on lightboost?

To add to the 7850 vs 660, this is worth looking at

http://www.anandtech.com/bench/Product/783?vs=778

At stock the 660 is a bit better with worse thermals/power consumption. rQwire is right, overclocking is more in the 7850's favor, and honestly graphics card overclocking is very easy right now (just fiddle with some sliders in ccc/afterburner/whatever) so you may as well. But nvidia typically is better with driver support and has lightboost in their favor.

They're both good cards, you're not going to be disappointed either way

FYI: the lightboost strobing feature is no longer Nvidia-centric

http://www.monitortests.com/forum/Thread-Strobelight-LightBoost-Utility-for-AMD-ATI-and-NVIDIA

All aboard AMD!