PSU question

Discussion in 'General Hardware' started by reppel, Dec 28, 2013.

  1. reppel

    reppel New Member

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    GPU:
    780ti sli
    When a power supply is marked as 750W, does this mean that it draws 750W from the wall at 100% or that it delivers 750W at 100% to the computer, which would in this case draw like 850W from the wall because of its 80-90% efficiency?
     
  2. Extraordinary

    Extraordinary Ancient Guru

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    GPU:
    ROG Strix 1080 OC
    Can deliver 750w to the PC

    But if you have a PC that will draw 750w - you want a 900w+ PSU
     
  3. reppel

    reppel New Member

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    Why 900+? Because of peaks and because it's tough for it to run at 100%?
     
  4. alanm

    alanm Ancient Guru

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    A PSU that runs at its peak generates more heat. Heat is the no.1 degrader of components, esp caps. So running it for extended periods at peak can shorten its lifespan.
     

  5. Extraordinary

    Extraordinary Ancient Guru

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    Always allow for some headroom, to be able run a 750w system at full load on a 750w PSU would be incredibly efficient, which systems are not, and PSUs are not

    Also hardware degrades over time, so after not too long, the PSU wouldn't be able to provide that full 750w

    a 900w+ PSU would have plenty of headroom to duck and dive so to speak

    Plus if you wanted to add another HDD or upgrade something, you'd be ok within a margin

    The PSU will only pull from the wall what it needs for the system, so don't worry that a 900w PSU will bankrupt you vs a 750w one
     
    Last edited: Dec 28, 2013
  6. eclap

    eclap Banned

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    Palit GR 1080 2000/11000
    depends on the psu.
     
  7. reppel

    reppel New Member

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    Than I guess I should buy a 1250W instead of 1000W for a 4930k and 2x 780ti on water.
    Sucks because it's more noisy.
     
  8. Extraordinary

    Extraordinary Ancient Guru

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  9. leeaids

    leeaids Active Member

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    GPU:
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    I would myself not wory about using a powersuply at full load as most are tested to be able to suply full load at the listed efficiency. I

    if its a decent make you should be fine
     

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