Again, these are just suggestions and things like the case, GPUor PSU are really up to you. Also, please note the RAM I selected here - large CPU coolers like the Noctua or Thermalright tend do get in the way of the Ram slots, so you are better off with low-profile bricks. Another thing to note is the PSU, which has modular cables, so any cable you don't need doesn't have to go in the case, makes for less clutter ^^
1 x Intel Core i5-3570K, 4x 3.40GHz, boxed (BX80637I53570K)
1 x Corsair Vengeance Low Profile blau DIMM Kit 8GB PC3-12800U CL9-9-9-24 (DDR3-1600) (CML8GX3M2A1600C9B)
1 x Gigabyte GeForce GTX 670 OC, 2GB GDDR5, 2x DVI, HDMI, DisplayPort (GV-N670OC-2GD)
1 x ASUS P8Z77-V, Z77 (dual PC3-12800U DDR3) (90-MIBHZ0-G0EAY0DZ)
2 x Noctua NH-U12P SE2 (Sockel 775/1155/1156/1366/AM2/AM2+/AM3/AM3+/FM1)
1 x Fractal Design Define R4 Black Pearl, schallgedämmt (FD-CA-DEF-R4-BL)
1 x OCZ ModXStream Pro 600W ATX 2.2 (OCZ600MXSP)
+ SSD and HDD
You can shave off ~100-200 Euros easily by taking a cheaper case and maybe a more mid-range GPU (like 560ti)