How much power do I eed

[Rodmantis]

I'm building my first system with the next parts (if you have advice on any of the parts, please say so)

CPU: Core i5 2500k.
GPU: ATI 6950 2GB Sapphire.
MOBO: ASUS P8Z68-V.
CASE: NZXT Phantom.
HDD: Seagate 1TB 7200 rpm.
RAM: Kingston HyperX or Corsair 2x4GB.

I plan on overclocking the i5 (not right away) and trying to flash the 6950 into a 6970, also I plan on adding an SSD in the future for the OS intallation.

How much power do I need, my salesman tells me to go secure and get a 900w, but I think even a 700w will be more than enough.

 

[sadams04]

650w would be plenty for a single GPU. Opt up for an 850w if you plan on adding a second GPU down the road.

 

[r0aringdrag0n]

Agree with sadams04:
Minimum I would use: 500W
Optimum: 650W
Crossfire: 800W
Overkill: 900W


Also remember to get a Brandname PSU, such as Seasonic, Corsair, or Antec. Don't Skimp on the PSU!

 

[Rodmantis]

thanks, yeah, many people have told me not to skim on the PSU and buy a known brand.

Here are the "best" options I have

600 Watts:
Thermaltake Performance 600W ATX 12V EPS at $70

650 Watts:
Cooler Master GX 650w
Antec EA650, both at $100.

700 watts:
OCZ StealthXStream at $117.76
Thermaltake TR2 700 at $126.

750 Watts:
Antec Earth Watts 4x12v at $115
Cooler Master GX 750 w 80 Plus at $120
Therlmaltake TR2 750watts at $129

900 Watts:
Antec High Current Gamer Series 900w 80 Plus Bronze at $159


Which one should I get for just overclocking the i5 and flashing the 6950 into a 6970, and which one should I get if I'd want to crossfire the 6950.

 

[sadams04]

Those are the best from your vendor? In that case...
Single GPU => Antec EA-650 (solid choice here!)
http://www.newegg.com/Product/Product.aspx?Item=N82E16817371044

Dual GPUs => Antec High Current Gamer 900w only because of the options you listed. If you can pull the CP-850 then go with that.
http://www.newegg.com/Product/Product.aspx?Item=N82E16817371024

Corsair, Antec, XFX or Seasonic are the manufacturers to consider if you can compare prices. Sizes stay the same at 650w and 850w respectively...

 

[Rodmantis]

I forgot to mention I don't live in the US, and those choices (for the price compared to other vendors) are pretty espectacular for my country. The thing is they don't carry 800 or 850 watt (they do but they are more expensive than the 900w one).

So out of THOSE i've listed in my last post. which one should i get

 

[sadams04]

Single GPU => Antec EA-650

Dual GPUs => Antec High Current Gamer 900w

 

[Rodmantis]

Best answer selected by Rodmantis.

 

[Rodmantis]

Single GPU => Antec EA-650

Dual GPUs => Antec High Current Gamer 900w

thank you for your answer