Is it ok to use a PSU rated higher than needed in a PC?

Discussion in 'Overclocking & Hardware' started by g12345567, Feb 29, 2020.

  1. g12345567

    g12345567 Member

    Joined:
    Nov 30, 2002
    Messages:
    714
    Location:
    Sydney Australia
    Was using a 650w power supply in my computer and it is being replaced under warranty by the manufacturer due to it not working properly with a 850w power supply.

    Thing is that my PC only uses at most 500w. Currently using a 550w 80+ gold PSU which is plenty. So thinking 850w will be overkill for my system.

    Just wonder what the effects are of using a power supply in a computer rated much higher than needed and will ever used?
     
  2. demiurge3141

    demiurge3141 Member

    Joined:
    Aug 19, 2005
    Messages:
    1,828
    Location:
    Melbourne 3073
    It's never a problem, you probably have a faulty PSU.
     
  3. power

    power Member

    Joined:
    Apr 20, 2002
    Messages:
    62,166
    Location:
    brisbane
    the PC will only use what it needs. only worry if the psu is rated at about what you need or below.
     
  4. dasa2

    dasa2 Member

    Joined:
    Feb 5, 2003
    Messages:
    760
    Location:
    Northern VIC
    PSU have a efficiency curve so it will use a bit more power outside of that but should also run a bit quieter when under load
    [​IMG]

    The system in your sig will use ~300w while gaming
    Maybe 400w if you overclocked and stress tested CPU\GPU\HDD all at the same time.
     
  5. power

    power Member

    Joined:
    Apr 20, 2002
    Messages:
    62,166
    Location:
    brisbane
    the other benefit of a higher capacity, high efficiency PSU is they don't work very hard. To give you an example I bought the RM1000i and under load on my overclocked 9700k/1080Ti system there isn't enough load for the fan to come on. I like this because it makes the system quieter as well.
     
    adamsleath, JSmithDTV and HobartTas like this.
  6. OP
    OP
    g12345567

    g12345567 Member

    Joined:
    Nov 30, 2002
    Messages:
    714
    Location:
    Sydney Australia
    As I said in my original post. Was using a 650w that stopped working correctly and its getting replaced under warranty with an 850w, which is a bit overkill. Thats why I wanted to know if there were any ramifications using it in a system that only uses at most 500w.
     
    Last edited: Feb 29, 2020
  7. power

    power Member

    Joined:
    Apr 20, 2002
    Messages:
    62,166
    Location:
    brisbane
    only benefits - PROVIDING, it has a good efficiency rating.

    so it depends on the exact PSU.
     
  8. sanjay

    sanjay Member

    Joined:
    Mar 10, 2004
    Messages:
    15,781
    Location:
    Maribyrnong, Melbourne
    It will be fine.
     
  9. Heatpipe

    Heatpipe Member

    Joined:
    Sep 2, 2008
    Messages:
    1,588
    If you look up the efficiency curve for the 850 watt psu you'll see at the highest load for your PC will be at the best efficiency for the psu. I.e 400w will yield 93% efficiency which means the psu will comsume 416w from the wall. TLDR You'll be fine.
     
  10. HobartTas

    HobartTas Member

    Joined:
    Jun 22, 2006
    Messages:
    905
    100% agree on this aspect about the fan!

    If we go back a decade or so when power supplies were at best bronze rated (90% efficient, 10% wasted as heat) I used to get power supplies that were about double the size required for the same reason Power just stated and going from a 550W-750W up to a 850W for a system that needed about 400W cost at most perhaps $50 extra and 850W were the sweet spot back then while the larger sizes after 850W then the price skyrocketed and you only ever needed those if you were using multiple video cards. These days with motherboards and especially CPU's being expensive like I9's I tend to only go for at the very minimum gold or preferably platinum rated power supplies as they are generally better quality. Its true the excess capacity with regards to "than needed and will ever used" is wasted but its a slightly higher one off capital cost and if you upgrade your CPU or video card you may find that you may need a bit more power later on so you have the extra capacity there, even if you don't upgrade you may decide to overclock stuff to make the PC last another 6-12 months so again you might need the extra juice.
     
  11. Zarok77

    Zarok77 Member

    Joined:
    Jan 2, 2020
    Messages:
    160
    Apparently they saying psu max efficiency at 50% load, so 500w system consumption = 1000w psu. Normally 850w is ok, unless funky vga bios are installed.

    Btw i have 9900k with 2080ti, d5 pump/7 system fan on 750w platinum rated psu that works just fine. Soon i will upgrade to at least 850w
     
  12. macktheknife

    macktheknife Member

    Joined:
    Jul 26, 2005
    Messages:
    840
    850w is a little overkill for a 550w system but no real issue.
     
  13. Bolter01

    Bolter01 Member

    Joined:
    Oct 14, 2008
    Messages:
    590
    Location:
    Ricktatership
    Nice one, I had ThermalTake replace a 1000w ToughPower after 2.9yrs use and a thunderstorm, and they gave me a 1200w ToughPower FTW!

    Seamless return +1 rep TT
     

Share This Page

Advertisement: