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How large of a PSU do i need?

I was wondering of how big a PSU i need. I used the http://www.extreme.outervision.com/PSUEngine calculator but I am not sure if it is right. It said i need 535W for my build and it didnt seem right.

cpu: i5-2500k oc: 5ghz if possible

video card: gtx680 i will try overclocking

ram: ddr3 2*4gb

motherboard: asrock z77 extreme6

hdd: 1tb 7200rpm 64mb cache

i just need to know if the results for the calculator are accurate or not and if not how to calculate the right amount of watts.
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More about large need
  1. For a system using a single GeForce GTX 680 graphics card NVIDIA specifies a minimum of a 550 Watt or greater power supply that has a combined +12 Volt continuous current rating of 38 Amps or greater and that has at least two 6-pin PCI Express supplementary power connectors.

    For a system using two GeForce GTX 680 graphics cards in 2-way SLI mode NVIDIA specifies a minimum of a 750 Watt or greater power supply that has a combined +12 Volt continuous current rating of 53 Amps or greater and that has at least four 6-pin PCI Express supplementary power connectors.

    Overclocking of the CPU and/or GPU(s) will require at least an additional 10 Amp increase to the combined +12 Volt continuous current ratings, recommended above, to meet the increase in power required for the CPU and GPU overclock that you are trying to achieve.


    Did you also see the eXtreme Power Supply Calculator Lite's disclaimer:

    ATTENTION:
    The recommended total Power Supply Wattage gives you a general idea on what to look for BUT it is NOT a crucial factor in power supply selection! Total Amperage Available on the +12V Rail(s) is the most important, followed by the +5V amperage and then the +3.3V amperage.

    The eXtreme Power Supply Calculator Pro version, that you have to pay for, contains Amperage per +12V, +5V and +3.3V power supply rails, recommended UPS rating, multiple video cards and more.
  2. Normal clocked system like yours would need about 400w so a 500+w PSU would be recommended to not be pushing your PSU to its limit... but since you are overclocking you need more power and I would recommend a 650w supply.

    This is for a quality supply that has enough amps to run your video card.
  3. Best answer
    abduizzle said:
    I was wondering of how big a PSU i need. I used the http://www.extreme.outervision.com/PSUEngine calculator but I am not sure if it is right. It said i need 535W for my build and it didnt seem right.

    cpu: i5-2500k oc: 5ghz if possible

    video card: gtx680 i will try overclocking

    ram: ddr3 2*4gb

    motherboard: asrock z77 extreme6

    hdd: 1tb 7200rpm 64mb cache

    i just need to know if the results for the calculator are accurate or not and if not how to calculate the right amount of watts.

    Did you use the overclock option when inputting data into the calculator ?
    It's only as accurate as the data it's given.
    AC power consumption of the GTX680 in a water-cooled, overclocked, extra bling X58 system when running a game like application : 307 watts
    http://www.guru3d.com/article/geforce-gtx-680-review/9
    Based on a 90% efficient psu that would be roughly a 50% load on a 550 watt psu.

    Unless you plan on running something like F@H or Furmark 24/7, a high quality psu with the Nvidia reccomended 550 watts / 38 amps / 2x 6 pin connectors would be fine.
  4. 5ghz? Custom watercooling!
  5. delluser1 said:
    Did you use the overclock option when inputting data into the calculator ?
    It's only as accurate as the data it's given.
    AC power consumption of the GTX680 in a water-cooled, overclocked, extra bling X58 system when running a game like application : 307 watts
    http://www.guru3d.com/article/geforce-gtx-680-review/9
    Based on a 90% efficient psu that would be roughly a 50% load on a 550 watt psu.

    Unless you plan on running something like F@H or Furmark 24/7, a high quality psu with the Nvidia reccomended 550 watts / 38 amps / 2x 6 pin connectors would be fine.


    Toms puts the systempower closer to 370w. overclocking the I5 to 5ghz would add roughly 100w and I'm not sure on how much extra would be needed to OC the 680. I suspect we'll be easily above 500w since 370 +100 =470 by itself. Hence my 650 recommendation.

    http://www.tomshardware.com/reviews/geforce-gtx-680-review-benchmark,3161-19.html
  6. popatim said:
    Toms puts the systempower closer to 370w. overclocking the I5 to 5ghz would add roughly 100w and I'm not sure on how much extra would be needed to OC the 680. I suspect we'll be easily above 500w since 370 +100 =470 by itself. Hence my 650 recommendation.

    http://www.tomshardware.com/reviews/geforce-gtx-680-review-benchmark,3161-19.html

    Tom's use's a less efficient psu and an overclocked 3960X
    The 3960x draws quite a bit more power than a 2500K when loaded
    Stock clocks
    http://www.tomshardware.com/reviews/sandy-bridge-e-efficiency-core-i7-3960x,3075-7.html
    http://www.tomshardware.com/reviews/core-i7-3960x-x79-sandy-bridge-e,3071-19.html
    http://www.anandtech.com/show/5091/intel-core-i7-3960x-sandy-bridge-e-review-keeping-the-high-end-alive/7

    Overclocked
    http://www.hardocp.com/article/2011/11/14/intel_core_i73960x_sandy_bridge_e_processor_review/8
    http://www.bit-tech.net/hardware/cpus/2011/11/14/intel-sandy-bridge-e-review/10
  7. Ok thanks you guys are a lot of help but is the power supplie good enough for my full system or do i need another +12v rail or somthin.

    http://www.newegg.com/Product/Product.aspx?Item=N82E16817139012
  8. Definitely good enough
  9. delluser1 said:
    Definitely good enough

    Thanks for all your help.
  10. Best answer selected by abduizzle.
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