I'm building a new pc under $520,need very good graphic card,psu,cabinet,hard disk,optical drive,motherboard for extreme gaming.I want to play games like BF3,Crysis-2 etc at max settings in a descent FPS.
AMD Phenom II X4 840 (I just got one of these for $59 US)
4-8gb DDR3 RAM
Western Digital Hard Drive
cheap DVD R/W drive
Antec 200 case
Corsair CX 430 power supply
Windows 7 Home Premium 64 bit OEM
Get the best video card you can with whatever money is left over. You can look at the video card charts on this web site to compare.
BTW, even though Newegg is not a shopping option for you, it is still a good site for research.