Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Is this power supply any good?

  1. Jan 20, 2013 #1
  2. jcsd
  3. Jan 21, 2013 #2
    NewEgg reviews are usually very trustworthy. I would go with that.
     
  4. Jan 22, 2013 #3
  5. Jan 22, 2013 #4
    Power supplies are one of the few remaining common scams to look out for with computer hardware which is why some cost ten times as much as others advertising the same output. A bad power supply can fry your entire computer and there are so many bad ones on the under-regulated market people are paying through the nose to buy quality ones from the few reputable manufacturers.

    A thousand watts is complete overkill and even 850w is more than almost anyone on the planet will ever need. For dual gtx 680s a 750w will suffice and the efficiency of the power supply goes down dramatically if you don't come anywhere near utilizing it's capacity. Raidmax is also not known for quality power supplies. Seasonic is perhaps the best name in the business, while Corsair is popular choice for both price and quality. If you want to save money on a power supply I'd focus on which brand names are reputable and wait for one to go on sale.
     
  6. Jan 22, 2013 #5

    Chronos

    User Avatar
    Science Advisor
    Gold Member

    A PSU is a terrible place to cut corners, as noted by wuliheron, considering most motherboards cost more than a decent PSU. I would stick to a known, reputable brand. An extra 20 or so bucks is worth the peace of mind. I also agree that 850W should be plenty, unless you also plan to use it to power a toaster oven and refrigerator. A good rule of thumb is to provide about twice as many watts as your system components will collectively draw.
     
  7. Jan 22, 2013 #6
    on an average computer (i'm over estimating to be safe)
    CPU (Full Load)
    ~100W
    Video Cards (Full Load)
    ~150W x2 = 300
    Hard Disk
    ~30W
    3-5 Case Fans
    ~25W (5W/fan)
    DVD Drive
    ~30W
    RAM (10W per module)
    ~40W

    So that works out to max power requirement:
    (100+300+30+25+30+40)W
    ≈ 525W

    You want your peak power requirements to be less than 80% of PSU capacity
    525/0.8 = 656W

    So, you can get away with a 650W PSU if you check and make sure there's no noise or spikes when it approaches full capacity.

    Get yourself a 750-850W PSU and you will never be anywhere near full capacity so you won't really have to even worry about it.
    If you have to spend an extra $50 bucks, do it, its a good investment and your system will thank you by not dying prematurely.

    1kW is overkill unless you plan on getting everything water cooled and need to run a pump running off the PSU

    The problem with budget PSUs, like the others have stated, is that it doesn't provide clean power, there's always some noise in the signal and depending on the fluctuations, it can be enough to damage your components. Look up reviews and tests of PSUs you are interested in, people hook them up to meters and set them to draw the max output possible and then measure just how clean the power is. If a PSU can supply clean power at max capacity, it will work great all the time. If a PSU can't, then i wouldn't trust my components to it.

    I have a bias for Corsair PSU's. This is the one that I've used when building systems for my friends.
    http://www.newegg.com/Product/Product.aspx?Item=N82E16817139006

    I have the 850W myself.
    http://www.newegg.com/Product/Product.aspx?Item=N82E16817139011
     
    Last edited: Jan 22, 2013
  8. Jan 22, 2013 #7
    The only way you could load your computer up to 100% capacity is to run Prime95 and Furmark simultaneously.

    But in nearly all computing situations, even enthusiast-level gaming graphics, will NOT use 100% of available computing resources.
     
  9. Jan 22, 2013 #8

    Chronos

    User Avatar
    Science Advisor
    Gold Member

    Concur on Corsair, their components are high quality, IMO. 850W is good enough for nearly any build that does not include a tanning bed ap. The '100% over wattage rule' is to allow your PSU to loaf - which extends its reliable service life. There is a reason 'bargain' PSU's have no more than a one year 'warranty'. Unless you plan to rebuild your system every year, they should be avoided.
     
  10. Jan 23, 2013 #9
    Yes, you are correct, however I'm trying to account for the widest range of possibilities. If the OP decided to over-clock the system, for example, burn-ins would be required. This is one case you would be coming close to peak usage.

    One needs to ensure that the PSU is able to work reliably in the one off extreme cases. Normal operation rarely ever is a problem but we need to prepare for those extreme cases because that's when the possibility of damage becomes significant enough.

    Setting the condition that the peak power requirements for the system are 80% or lower than the PSU's max output, you effectively rule out the possibility of damage as long as its a good PSU. That is my rule of thumb when building systems and advice to anyone looking for information.
     
  11. Jan 23, 2013 #10
    High-quality PSU's such as the ones made by Corsair, are designed to last much longer than 5 years.
     
  12. Jan 23, 2013 #11
    5 years! That's gonna be one old system! :)
     
  13. Jan 23, 2013 #12
    Yup, but it better have a top-notch PSU to power it long enough before it becomes laughably obsolete.

    It would still be alive and kickin' when it should be donated to a museum.
     
  14. Jan 24, 2013 #13
    Corsairs are rated to last ten years of continuous use and by the time the thing dies it will be so obsolete it isn't funny. Quality power supplies also tend to have much better built in protection from wall sockets helping to protect the entire computer. Add a quality surge protector and most people are good to go, but in places with bad lightening storms many people recommend using a more expensive UPS surge protector.
     
  15. Jan 25, 2013 #14

    Chronos

    User Avatar
    Science Advisor
    Gold Member

    Surge protectors are cheaper fuses than your computer system components.
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook




Similar Discussions: Is this power supply any good?
  1. TP600 power supply (Replies: 0)

  2. Power supply (Replies: 3)

  3. Power supply failure? (Replies: 3)

Loading...