Build Advice Good desktop build setup?

Hi guys, first time making a pc setup. I want to use it mostly for gaming.

case: Antec 300
supply: CoolerMaster GX Series Power Supply / 650W
motherboard: Asus 1155 P8 P67 (rev.3) S/GBL/R/DDR3/USB3/ATX
CPU: intel 2500k I5
RAM: 8192MB DDR3/1333 Corsair XMS CL9 KIT
Optical: Sony Optiarc AD5260s 24x SATA
HHD: 1,0TB WesternDigital WD10EALX 32/SATA3
graphic: nVidia Asus GTX570 DCII 2x DVI/HDMI/GDDR5 1280MB
after market cooler: The cooler master hyper 212

Suggestions are welcome too, thanks!