What Wattage PSU should i get?

cscoxy

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Oct 18, 2010
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Hi guys, I am wondering what wattage i should go for in a PSU for my new setup:

i7 920 OC @ 4.01Ghz
MSI X58 PRO MB
OCZ 3x2G DDR3 10666 Platinum 7-7-7-20 @1600MHz
XFX HD5970 2G GDDR5 BE
OCZ 120G Vertex II E Series SSD
Seagate SATAII 1.5T 7200RPM HDD
Corsair H70 (both fans in use)
Antec 900 (3x 120mm + 1x 240mm fans)
Usually have around 5 usb devices in use (mouse,Kb,cans etc).

Thanks for any recommendations!
 

cscoxy

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Oct 18, 2010
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Nice, cheers for the quick answers guys! Was actually worried that 850 would not be enough with the 5970...

I was looking at XFX 850W Black Edition Modular PSU after reading a good review, otherwise the Corsair HX 850...

Is 850 overkill or reasonable?
 

insightdriver

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Nov 28, 2006
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For a power supply, there are plenty of online power supply calculators where you enter your components and it adds up all the wattage requirements of each you enter. Using a calculator, you can add what you might want to have added in the future, such as a second video card, etc. I tend to add about 10% over that number for margin. It makes no sense to have a power supply way too big (cost goes up), and you certainly don't want a power supply to be too small.

Think of it this way, give a man a fish, he eats for a day, teach a man to fish, well, you get the idea.

(added in edit, when it came to me)
my setup is similar to yours and I had an 850W Corsair power supply. When I calculated what I needed, including a second graphics card, and taking into account the overclocking I am doing; the calcuators I used gave me 820watts that I needed. Understand, too, that is maximum power you need; most of the time a computer as you use it is only idling along using less than half that value.
 

cscoxy

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Oct 18, 2010
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I Checked out a cpl of these and they all seem to come up different. One gave me 820 ish, which is why i was originally thinking 850 might be cutting it fine and i should go higher...

Cost isn't really an issue, supplying enough and stable power to my comp is ;). Am in Australia as well so prices are crap anyway :s. XFX 850 is going for
$205 and Corsair HX850 $222.
 
Unless you plan on adding an extra GPU the 650 is OK as long as the PSU is a "GOOD" psu (Corsair, Seasonic.

Your Power consumption should be around 200 W Idle and 500 Watts running Furmark, gaming should be somewhat Less.
Ref (System with an i965 Extreme Ed @ 3.7 Ghz W/ 700 W OCZ PSU))
http://www.techspot.com/review/221-ati-radeon-hd-5970/page15.html

I find that the PSU calulators provide a Higer than what is really need as a "safety Factor" to compensate for the POOR PSUs out there.