Which PSU to buy?

Hardware Hub PSU
1

This is for a build with a 3570k and a 7950 or maybe a 7970. I read that the 500w range would be perfect since I don't plan on a dual gpu configuration.

I found these three that are within my price range:

http://www.amazon.co.uk/OCZ-OCZ500MXSP-UK-ModXstream-Power-Supply/dp/B001GLFD4U/ref=sr_1_5?ie=UTF8&qid=1377872270&sr=8-5&keywords=500w+psu+modular#productDetails

http://www.amazon.co.uk/Zalman-ZM550-XG-Modular-Power-Supply/dp/B007MJGE52/ref=sr_1_10?ie=UTF8&qid=1377872270&sr=8-10&keywords=500w+psu+modular#productDetails

http://www.amazon.co.uk/Aerocool-GT-500SG-Cable-Modular-Warranty/dp/B0096XSLSA/ref=sr_1_5?s=computers&ie=UTF8&qid=1377872845&sr=1-5&keywords=aerocool+psu

Which one do you think I should get? 

2

I wouldn't really use any of those. What is your budget? 500W is about 130W too large, as well, for a single GPU configuration.

3

http://www.amazon.co.uk/dp/B005FPT38U/?tag=pcp0f-21

Get the 550W variant if you want the headroom

http://www.amazon.co.uk/ProSeries-550W-Power-Supply-Edition/dp/B004U6S1P6/ref=sr_1_4?s=computers&ie=UTF8&qid=1377876588&sr=1-4&keywords=xfx+550