800rupees

my system spec as follows: Cpu- amd phenom x4 9650 2.3ghz Vga- HIS HD6670 1gb gddr5 Ram- 2x2gb ddr2 HDD- 2Xsamsung 320gb psu- techcom 460watt dvd writer with motherboard asus m2n68-am plus. i want to upgrade my psu but i m confused which one is will be better. corsair vs450 is good for...