Corsair 2x4gb, 1600mhz CL 9-9-9-24
PSU: haswell certified is Corsair CX750 (750 watt PLENTY)
Cooling Corsair h100i, if you must watercooled.... would save the money and try and get a Samsung 840 pro SSD 128 gigs.
Most NOTICABLE performance upgrade sinds years.
Let me know if you need anything else (Y).
Nice videocard btw, got it myself too on my 1300 euro build!
I was asking the OP, because he may have his own reasons. I would like to hear his reasons and try to persuade him to use his own labor to get better performance. Normally, if you follow all the steps to building a pc correctly, there should be no problems unless you buy bad quality parts or get a DOA part (which is very very unlikely).
Choosing a gpu isn't very hard. This forum is meant to help you choose the correct components.
Is there any reason why you prefer pre-built? It limits your choice options as well as making it more expensive.
I'm just nervous about building it myself. I've put graphics cards and RAM in before. But that's like putting a cartridge in to a NES. It's the motherboard, and CPU I'm scared of. I've heard it doesn't really matter if you go prebuild, or build it. Sometimes you can save a little.
I know components, but I don't really have time to build it or study how to do it.