1. Welcome to TechPowerUp Forums, Guest! Please check out our forum guidelines for info related to our community.

PSU gets hotter after shutdown.

Discussion in 'General Hardware' started by slyfox2151, Jun 7, 2010.

  1. slyfox2151

    slyfox2151

    Joined:
    Jan 14, 2009
    Messages:
    2,606 (1.30/day)
    Thanks Received:
    524
    Location:
    Brisbane, Australia
    Hello,
    watch this video (2:45 seconds into the video to be precise)
    http://www.techpowerup.com/124012/T...hpower_Grand_80_PLUS_Gold_Certified_PSUs.html



    according to there test, a random brand PSU without there delay cool "technology -.-" will incress from 50 C to nearly 70 C in tempreture when you turn it off, is this really correct?


    after you shutdown the PC and the PSU turns off, why would the tempreture incress if the heat production has stoped? the air would get warmer yes but the componets them selves should get cooler not hotter.


    is this a flaw in the way they messure the temp / gimmic?
  2. NdMk2o1o

    NdMk2o1o

    Joined:
    Apr 21, 2010
    Messages:
    3,444 (2.23/day)
    Thanks Received:
    922
    Location:
    Redditch, Worcestershire, England
    That graph shows a typical psu as being the red line when turned off the fan stops immediately and the components heat up initially, the one he is talking about is the blue line where the fan stays on longer so you dont have the jump in temps.

    Thats what they say, though it only spun for 2-3 seconds after it was turned off from what I saw?
  3. slyfox2151

    slyfox2151

    Joined:
    Jan 14, 2009
    Messages:
    2,606 (1.30/day)
    Thanks Received:
    524
    Location:
    Brisbane, Australia
    im assuming the video was cut to reduce its size/time? or its just a flaw / bug there going to work out.



    i know that the blue line is there psu and the red is a random psu. that was not my question, why would it get hotter?

    if you cut the power, no more heat is being made. why would it get hotter if its not using power? this goes agenst the laws of thermodynamics.


    if you cut the source of heat at the same time you slow and stop the cooling. it would not get hotter.
  4. AsRock

    AsRock TPU addict

    Joined:
    Jun 23, 2007
    Messages:
    10,692 (4.15/day)
    Thanks Received:
    1,623
    Location:
    US
    That TT would probably stay hotter than most longer due to the lame ass heatsinks it has inside it lol.

    I would have to say it make little or no difference if the heatsink(s) can handle the heat and remove it.
  5. Mussels

    Mussels Moderprator Staff Member

    Joined:
    Oct 6, 2004
    Messages:
    41,942 (11.76/day)
    Thanks Received:
    9,364
    it really doesnt matter. they're skewing the results.


    All this means is that their PSU with the delay will cool down to ambient quicker... which doesnt really mean anything. the PSU was operating at those temps, so how is it going to harm it?

    heat production simply doesnt continue with the system off, so the temps dont increase on the HARDWARE, but the *air* in the PSU case might - heat is still leaving the PSU components and travelling into the air, but not being pushed out of the enclosure. so the PSU itself is cooling down quite nicely, its the air that isnt.

    If you dont get how that works, think of it this way: your bladder is full of hot, steaming urine. you take a piss. suddenly, the toilet waters temperature rose. OH NO. but you (the source of the heat) just dumped a ton of heat out of you... so you're cooler. its just the area around you that got warmed up.


    dont forget that sudden changes in temp causes expansion/contraction, which is what slowly kills hardware by cracking solder joins and so on. IMO its best to let it slowly cool down over a minute or two, than their method.
  6. claylomax

    claylomax

    Joined:
    Apr 10, 2010
    Messages:
    1,586 (1.02/day)
    Thanks Received:
    255
    Location:
    London
    In my opinion that fan delay thing is just a gimmick, some marketing thingy.
  7. AsRock

    AsRock TPU addict

    Joined:
    Jun 23, 2007
    Messages:
    10,692 (4.15/day)
    Thanks Received:
    1,623
    Location:
    US
    +2

    Did not think of that till you said it.. Dry joints is a killer.
  8. Athlonite

    Athlonite

    Joined:
    Jan 31, 2010
    Messages:
    1,913 (1.18/day)
    Thanks Received:
    480
    My Hiper TypeR 580 has a tiny 70mm fan on it that stays going for ~2mins it doesn't move a shit load of air but just enough so that some cooler air is being dragged into the PSU for the last 12mnths no problems here with cracked solder joints as yet and it usually runs around the 60~70% mark all the time so fairly warm although now I have my RV02 case and it sucks cool air in from outside the case i have noticed a considerable temp drop off
  9. dr emulator (madmax)

    dr emulator (madmax)

    Joined:
    May 5, 2009
    Messages:
    2,241 (1.18/day)
    Thanks Received:
    176
    Location:
    the uk that's all you need to know ;)
    i remember some time ago a psu that reportedly exhausted the hot air for a while after you switched the pc off, i think it was a hyper or something of a similar name, haven't heard of it since though
    i have the side of my case off anways so it would be a pretty useless gimick tbh
    as for psu's heating up, well i think that's inevitable (i usually switch mine off at the wall) so :rolleyes:
  10. Bo$$

    Bo$$ Lab Extraordinaire

    Joined:
    May 7, 2009
    Messages:
    5,271 (2.78/day)
    Thanks Received:
    854
    Location:
    London, UK
    well most expensive psus do that, even this cheiftec one does

Currently Active Users Viewing This Thread: 1 (0 members and 1 guest)

Share This Page