Even in Euro that is a good amount for a quality PC.
Case:
Cooler Master HAF 932 - This is a full ATX case, great for large GPU's. €119.95
Motherboard:
ASUS SABERTOOTH 990FX - This is not yet in stock, but should be soon. This is an AMD 990FX board putting it in their enthusiast class. Any motherboard with 990FX is best for multiple graphics cards, unlike the less expensive 970 boards. If you don't see yourself using more than one GPU, you can save money by going with those boards as they are very similar. €159.95
CPU:
AMD FX 8120 Black Edition 3.1GHz - This is one of AMD's best processors. €159.95
ODD:
Asus DVD Burner 24B5ST - You just need a basic one. €29.95
RAM:
Corsair Value Select - 4GB 1333MHz PC3-10600 - I would get two of these for a total of 8GB. €26.95 per stick (€53.90 for two)
GPU:
MSI GeForce N670GTX-PM2D/OC - This GTX 670 graphics card is one of the best on the market. €407.00
OS:
Microsoft Windows 7 Home Premium SP1 64 bit OEM UK - You need this. €98.95
PSU:
Corsair - Enthusiast Modular TX650M - If you were going to be using more than one graphics card, I would go for a 750W, but this is more than enough for your current build. €97.95
HDD:
Seagate 500GB SATA-600 - Normally, I would get an SSD to supplement this, but your budget prevents that. However, this should be adequate for your needs. €79.95
Grand Total €1,207.55