New build for semi-gaming, opinions needed.

This build I have already ordered from Verkkokauppa.com, and I just want to hear opinions and if people have any thought on the build. The order can still be modified, so good ideas for the build are welcome. My older build is like over 5 years old with the only upgrade being radeon HD5450 from radeon X1950.

The build is for semi-gaming; I play games but lower graphics are fine for me if I play some new game.

A new HD: Western Digital Caviar Blue 500GB SATA3 7200RPM 16 - 88,90 €
GPU: Asus EAH6870 DC/2DI2S/1GD5 Radeon HD 6870 1GB GDDR - 185,90 €
Motherboard: Asus Sabertooth 990FX AM3+ ATX - 159,90 €
CPU: AMD FX-4100 3.6 Ghz 4-core Black Editon AM3+ - 120,90 €
Power: Antec TruePower New TP-750 750W ATX-virtalähde.80P - 132,90 €
Memory: Corsair Vengeance 8 GB Kit PC3-15000, 1866 MHz, 2x - 70,90 €

Sum: 759,40 €

Any ideas for this system?

Thanks in advance.

EDIT:

Approximate Purchase Date: Waiting for parts

Budget Range: 600-800€

System Usage from Most to Least Important: surfing the internet, gaming, watching movies, BOINC)

Parts Not Required: keyboard, mouse, monitor, speakers, OS

Preferred Website(s) for Parts: Verkkokauppa.com

Country: Finland

Parts Preferences: AMD/ATI

Overclocking: Yes

SLI or Crossfire: Maybe

Monitor Resolution: 1920x1080

Additional Comments: Energy efficiency is cool.