Please help me decide on wattage for this system:

Please help me decide what wattage I need for the following system. I used the non-detailed Newegg calculator which suggested 400W and the eXtreme power calculator (http://extreme.outervision.com/PSUEngine) which suggested ~380W (factoring in: overclocking, future SSD, future USB device, wireless NIC, and randomly selected 3 case fans because I don't have a case yet). I don't plan on using Crossfire. Do these wattage suggestions seem low to you? Should I be safe and go with a PSU with a lot higher wattage than suggested? Do these suggestions consider extras such as webcams, flash drives, etc. that will also be plugged in?

I would also appreciate any specific PSU recommendations.

I've already purchased the following components:

Brains: Intel i5-2500K
http://www.newegg.com/Product/Product.aspx?Item=N82E16819115072

Mobo: Gigabyte Z77-D3H
http://www.newegg.com/Product/Product.aspx?Item=N82E16813128543

RAM:
G.SKILL Ripjaws X Series 8GB (2 x 4GB) DDR3 1600 MHz
http://www.newegg.com/Product/Product.aspx?Item=N82E16820231428

GPU:
SAPPHIRE Radeon HD 6850 1GB
http://www.newegg.com/Product/Product.aspx?Item=N82E16814102908

HDD:
Western Digital Caviar Black 1TB 7200 RPM SATA3 64MB cache
http://www.newegg.com/Product/Product.aspx?Item=N82E16822136533

Cooling:
COOLER MASTER Hyper 212 Plus
http://www.newegg.com/Product/Product.aspx?Item=N82E16835103065

Oh, and I have a DVD-RW drive (LG GSA-H10a) harvested from an old computer.

Thanks!
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More about please decide wattage system
  1. Scraniel said:
    Please help me decide what wattage I need for the following system. I used the non-detailed Newegg calculator which suggested 400W and the eXtreme power calculator (http://extreme.outervision.com/PSUEngine) which suggested ~380W (factoring in: overclocking, future SSD, future USB device, wireless NIC, and randomly selected 3 case fans because I don't have a case yet). I don't plan on using Crossfire. Do these wattage suggestions seem low to you? Should I be safe and go with a PSU with a lot higher wattage than suggested? Do these suggestions consider extras such as webcams, flash drives, etc. that will also be plugged in?

    I would also appreciate any specific PSU recommendations.

    I've already purchased the following components:

    Brains: Intel i5-2500K
    http://www.newegg.com/Product/Product.aspx?Item=N82E16819115072

    Mobo: Gigabyte Z77-D3H
    http://www.newegg.com/Product/Product.aspx?Item=N82E16813128543

    RAM:
    G.SKILL Ripjaws X Series 8GB (2 x 4GB) DDR3 1600 MHz
    http://www.newegg.com/Product/Product.aspx?Item=N82E16820231428

    GPU:
    SAPPHIRE Radeon HD 6850 1GB
    http://www.newegg.com/Product/Product.aspx?Item=N82E16814102908

    HDD:
    Western Digital Caviar Black 1TB 7200 RPM SATA3 64MB cache
    http://www.newegg.com/Product/Product.aspx?Item=N82E16822136533

    Cooling:
    COOLER MASTER Hyper 212 Plus
    http://www.newegg.com/Product/Product.aspx?Item=N82E16835103065

    Oh, and I have a DVD-RW drive (LG GSA-H10a) harvested from an old computer.

    Thanks!

    Not really
    See power consumption of a 2500K and 6870 here
    http://www.silentpcreview.com/article1245-page3.html
    237 watt DC load when running a pair of power viruses
    The psu calculator provides a safe wattage reccomendation, not the 50% or more overage that many claim you must have for optimal efficiency and extended psu life
  2. A system with an HD 6850 requires a 500W PSU with a minimum of 28A available on the 12V rails and one 75W 6-pin PCIe power connector; Amps on the 12v rails is more important than the wattage rating of the PSU. There are good quality 400W PSUs that have the required amount of amerage on the 12V rails, like the PC P&C MKIII 400W. The 380W Antec EA-380D also meets the minimum requirements.

    If you plan on OCing the CPU or GPU, then you should get a PSU with more amperage available on the 12v rails. The Seasonic M12II-520 is a great PSU and Newegg has it at a great price right now: http://www.newegg.com/Product/Product.aspx?Item=N82E16817151093&Tpk=m12ii-520
    That is the PSU that I'd recommend.
  3. Rugger said:
    A system with an HD 6850 requires a 500W PSU with a minimum of 28A available on the 12V rails and one 75W 6-pin PCIe power connector; Amps on the 12v rails is more important than the wattage rating of the PSU. There are good quality 400W PSUs that have the required amount of amerage on the 12V rails, like the PC P&C MKIII 400W. The 380W Antec EA-380D also meets the minimum requirements.

    If you plan on OCing the CPU or GPU, then you should get a PSU with more amperage available on the 12v rails. The Seasonic M12II-520 is a great PSU and Newegg has it at a great price right now: http://www.newegg.com/Product/Product.aspx?Item=N82E16817151093&Tpk=m12ii-520
    That is the PSU that I'd recommend.


    @Rugger, thanks for the great suggestion! I really like the looks of that PSU.

    By the way, how did you know those nuances of the power requirements of the Radeon 6850? Where can I find that information? More importantly, where can I find similar power information (amperage requirements) for the other components (or are the other components irrelevant in that regard)?
  4. That figure is for a system with 6850.
  5. Hi :)

    500w..

    All the best Brett :)
  6. 450 will do it. I used the power supply calculator.
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