1100 euros will get you a whole lot more computer.
First of all, no reason at all to get a CLC, especially the Corsair series. Invest in a high-end air cooler, like a Phanteks PH-TC14PE, Silverarrow Extreme, Noctua NH-D14, bequiet! Dark Rock Pro 2, etc., and you will have a quieter, higher-performing cooler for, usually, less money.
CPU-wise, it looks like you want mATX, and I'm a fan. I would recommend going for Haswell, simply because it gets better performance per-clock, but that is just me. The ROG series of mATX boards, the Gene line, as you chose, are great for overclocking and have a solid overall feature set. If you want even smaller, the Haswell Z87 Impact is an ITX ROG board that can crank out just as high of OCs, albeit, it is more expensive.
For cases, in the mATX size, there really isn't any competition at the price-range against the Silverstone TJ08B-E. PcPartPicker doesn't have it, so I added it as a custom part from Amazon.co.uk down at the bottom of the list. It is aluminum, and much better than the aluminum-can sheet that Lian Li uses on their low-end cases. It has plenty of room for full-sized PSUs, holds an ample amount of drives, and even supports decent watercooling options (a 180 and 120mm rad out of box, which is plenty for CPU + GPU). Fantastic choice, both aesthetically, functionally, and for the price.
GPUs are tricky; with R9 having just come out, the price of 79xx has dropped exponentially. You can easily fit 7950 CF in that budget, which will destroy a 7970 or 680. Power draw will be reasonable, especially with Haswell, so any decent 650W PSU will be plenty. If you would rather go for a single 7950, which, mind you, will max out 99% of games at 1080p, then you could fit more storage, more fans, and other "goodies" into the rig. If you want dual 7950s, I would recommend a Lepa G650. It is one of the highest quality OEMs that CWT produces, up there with the Enermax OEMs that Lepa uses on many of their other G series PSUs. It has a low ripple, high efficiency, and delivers the appropriate wattage and amperage on the single +12V rail for dual GPUs, as well as the appropriate connectors for up to 4 8-pin PCIe connectors. Fantastic unit, one that I would use in any rig. If you want a single 7950, you don't need 650W, so you could grab a smaller unit, like an XFX Core 450, which, although lower quality, is still fantastic for the price, and saves money for other things in the rig, or just money in your pocket. Another great unit to consider is the Fractal Design Telsa R2 650; again, great ripple, efficiency, and at a very competitive price.
As for the RAM, I would go for 8GB of G.SKILL Sniper 1866mHz CL9 @ 1.5V, that way it is small enough for even the largest CPU cooler, like the bequiet! Dark Rock Pro 2 I included for the amazing performance and stunning looks (it should fit, seeing as physically, it is roughly the size of the NH-D14, which definitely fits.) Fast, low CL, low voltage, plenty of it.
Lastly, I threw in another fan, a 120mm Scythe Gentle Typhoon, which has reasonable CFM, great noise, incredible quality, and, were you to ever watercool, would work fantastically as a radiator fan. I would use it as rear exhaust, because back fan grills, generally, are pretty restrictive.
Rig with dual 7950s: http://uk.pcpartpicker.com/p/1HS2l
Rig with single 7950s: http://uk.pcpartpicker.com/p/1HRP0
Hope that helps some!