Personally, I'd swap out the CPU for an AMD FX-6300. The AMD platform tends to be cheaper, plus AMD CPU's have better value (FPS per $, or GBP in your case.). Also, it's more balanced. Why would you pair an otherwise top-end (gaming) CPU with a mid-range GPU? The FX-6300 is midrange, and it OC's should you need the extra performance. From what I hear, AMD is significantly cheaper than Intel internationally, but I haven't really checked.
Also, I'd get lower speed, lower latency RAM. 2133 is pretty unecessary in gaming, especially with mid-range hardware. Latency makes a larger impact at that level. I'd go for 1600 CAS 9, or 1866 CAS 9, or 10.
Id get 1600 or 1866 ram and a case with a better designe and airflow like a define R4, oh and a corsair,XFX,seasonic or silverstone PSU, if not one of those get 80+ bronze minimum.
ok if you are overclocking (you are going with a k cpu so i know you are) the sabertooth is extremly stable so if you have a few extra quid lying around in the couch get the better mobo ( i know you do have a few quid lying around becouse i lost quite a bit when i was in the uk )
Deff take a look at your PSU selection. I have been one who always skimmped on my PSU choice thinking it didnt matter and learned the hard way. It really is one of if not the most important piece of the puzzle. Dosent have to be a 1000 watt psu but by a solid company and beyondnight has some great suggestions there but PC Power& Cooling deserves a mention I think. They are basically OCZ manufactured but with way better quality componets and are work horses. PSU is an inportant componet no doubt.....
C'mon guys, keep things in perspective! Some of these recommendations on the PSU are really irritating. All you need is 600w, and that should cover a 7870 and overclocking on both the CPU and GPU. Just make sure it's a reliable single rail 80plus PSU, and you're good. A single 7970GHz OC'd with OC'd CPU could still be handled with relative ease on a solid 650w. About the only reasons to need more than a 650w is SLI/Crossfire, a massive storage array, or some very elaborate cooling.
The 8350 will not bottleneck a 7970. In terms of gaming, Logan has showed that 8350 is actually better on some titles, and for the most part, trade blows with Intels Core i7's 3770k and 3820 with the 7870 AND GTX 670. So unless the higher power draw really bugs you, I don't any reason to pick the 3570k over an 8350 given the difference in value. If you can find a 3570k for under $200, then either way, but as long as that 3570k remains at $230 I'm going to have some trouble recommending that CPU over the FX in any sort of value/budget machine (<$1200), especially in light of real-world gaming performance.
And some of the motherboards I'm seeing recommended are really overkill, especially on a TX3 cooler. Any mainstream board (~$100 - $150) should do the trick. That cooler will give you problems overclocking before even a budget board ($60-$100) will, so it really doesn't make any sense to dump $180+ in a motherboard unless you really need the I/O.