Let me give some advice on PSU purchases.
You guys seem to think its all about Wattage when in actual fact its the Amps on the 12v rail that is most important.
That's why using a power supply calculator is useless.
Some psu's offer 750W but a crappy 36amps on the 12v rail and it'll cost you around R800, so compare that to a Corsair TX750 which is a 750W psu, that offers 60 amps on the 12v rail and it'll set you back around R1200.
Also take note a PSU is probably the single most important piece of hardware in a pc. A high quality psu is essential.
Eat - Sleep - Overclock - Repeat