Huh? PSU question.

Discussion in 'NZ Computing' started by Matthew Poole, Jul 11, 2004.

  1. In article <OT2Ic.9563$>, "~misfit~" <> wrote:
    *SNIP*
    >I've only just examined it a bit more closely. It's a "Texconn KY-5 00ATX
    >400 WATT Power Supply" in large letters. Then, in *a lot* smaller letters
    >below is has Output (Max): +3.3v 26A, +5v 30A, +12v 12A, -12v 0.5A, -5v
    >0.8A, +5vsb 2A.
    >
    >Ok, I'm not that electrically minded (so to speak) but isn't that +12v
    >figure a little low, considering it has "P4" in large letters on the side
    >and has the 12v four-pin CPU power connector? Considering the power draw of
    >a modern CPU, surely there wouldn't be much left of that 12A on the +12v
    >left for drives etc.
    >
    >Maybe I'm all wet on this one.


    The drives all run off the 5V and 3.3V rails. Hence the high amp
    ratings for those. The 12V stuff is just there for the CPU, so 12A is
    heaps, even when feeding one of the latest monstrosities to come from
    Intel.

    --
    Matthew Poole Auckland, New Zealand
    "Veni, vidi, velcro...
    I came, I saw, I stuck around"

    My real e-mail is mattATp00leDOTnet
     
    Matthew Poole, Jul 11, 2004
    #1
    1. Advertising

  2. Matthew Poole

    ~misfit~ Guest

    I picked up a PSU yesterday as a replacement for an el-cheapo that blew up
    under warranty. The one that blew was a "Leaf" brand, 400W. The shop took it
    out back, tested it, looked at my receipt, then gave me another, new, PSU. I
    galnced at it, saw it was a different brand but had "400 WATT" in large
    letters on the label and came home.

    I've only just examined it a bit more closely. It's a "Texconn KY-5 00ATX
    400 WATT Power Supply" in large letters. Then, in *a lot* smaller letters
    below is has Output (Max): +3.3v 26A, +5v 30A, +12v 12A, -12v 0.5A, -5v
    0.8A, +5vsb 2A.

    Ok, I'm not that electrically minded (so to speak) but isn't that +12v
    figure a little low, considering it has "P4" in large letters on the side
    and has the 12v four-pin CPU power connector? Considering the power draw of
    a modern CPU, surely there wouldn't be much left of that 12A on the +12v
    left for drives etc.

    Maybe I'm all wet on this one.
    --
    ~misfit~
     
    ~misfit~, Jul 11, 2004
    #2
    1. Advertising

  3. Matthew Poole

    Harry Guest

    ~misfit~ wrote:

    > I picked up a PSU yesterday as a replacement for an el-cheapo that blew up
    > under warranty. The one that blew was a "Leaf" brand, 400W. The shop took
    > it out back, tested it, looked at my receipt, then gave me another, new,
    > PSU. I galnced at it, saw it was a different brand but had "400 WATT" in
    > large letters on the label and came home.
    >
    > I've only just examined it a bit more closely. It's a "Texconn KY-5 00ATX
    > 400 WATT Power Supply" in large letters. Then, in *a lot* smaller letters
    > below is has Output (Max): +3.3v 26A, +5v 30A, +12v 12A, -12v 0.5A, -5v
    > 0.8A, +5vsb 2A.
    >
    > Ok, I'm not that electrically minded (so to speak) but isn't that +12v
    > figure a little low, considering it has "P4" in large letters on the side
    > and has the 12v four-pin CPU power connector? Considering the power draw
    > of a modern CPU, surely there wouldn't be much left of that 12A on the
    > +12v left for drives etc.
    >
    > Maybe I'm all wet on this one.


    The CPU runs off the 3.3v.

    3.3*26 + 5*30 + 12*12 + 12*0.5 + 5*0.8 +5*2 = 399.8 watts
     
    Harry, Jul 11, 2004
    #3
  4. Matthew Poole

    Harry Guest

    Matthew Poole wrote:

    > In article <OT2Ic.9563$>, "~misfit~"
    > <> wrote: *SNIP*
    >>I've only just examined it a bit more closely. It's a "Texconn KY-5 00ATX
    >>400 WATT Power Supply" in large letters. Then, in *a lot* smaller letters
    >>below is has Output (Max): +3.3v 26A, +5v 30A, +12v 12A, -12v 0.5A, -5v
    >>0.8A, +5vsb 2A.
    >>
    >>Ok, I'm not that electrically minded (so to speak) but isn't that +12v
    >>figure a little low, considering it has "P4" in large letters on the side
    >>and has the 12v four-pin CPU power connector? Considering the power draw
    >>of a modern CPU, surely there wouldn't be much left of that 12A on the
    >>+12v left for drives etc.
    >>
    >>Maybe I'm all wet on this one.

    >
    > The drives all run off the 5V and 3.3V rails. Hence the high amp
    > ratings for those. The 12V stuff is just there for the CPU, so 12A is
    > heaps, even when feeding one of the latest monstrosities to come from
    > Intel.
    >


    Rubbish. Drives run off +5/+12 volts at about 0.5A/1A respectively.
    But you are correct that the CPU uses +12v also.
     
    Harry, Jul 11, 2004
    #4
  5. Matthew Poole

    Harry Guest

    Harry wrote:

    > ~misfit~ wrote:
    >
    >> I picked up a PSU yesterday as a replacement for an el-cheapo that blew
    >> up under warranty. The one that blew was a "Leaf" brand, 400W. The shop
    >> took it out back, tested it, looked at my receipt, then gave me another,
    >> new, PSU. I galnced at it, saw it was a different brand but had "400
    >> WATT" in large letters on the label and came home.
    >>
    >> I've only just examined it a bit more closely. It's a "Texconn KY-5 00ATX
    >> 400 WATT Power Supply" in large letters. Then, in *a lot* smaller letters
    >> below is has Output (Max): +3.3v 26A, +5v 30A, +12v 12A, -12v 0.5A, -5v
    >> 0.8A, +5vsb 2A.
    >>
    >> Ok, I'm not that electrically minded (so to speak) but isn't that +12v
    >> figure a little low, considering it has "P4" in large letters on the side
    >> and has the 12v four-pin CPU power connector? Considering the power draw
    >> of a modern CPU, surely there wouldn't be much left of that 12A on the
    >> +12v left for drives etc.
    >>
    >> Maybe I'm all wet on this one.

    >
    > The CPU runs off the 3.3v.


    Sorry, my mistake - the CPU also uses +12v (at 10A).

    >
    > 3.3*26 + 5*30 + 12*12 + 12*0.5 + 5*0.8 +5*2 = 399.8 watts
     
    Harry, Jul 11, 2004
    #5
  6. Matthew Poole

    MarkH Guest

    "~misfit~" <> wrote in
    news:OT2Ic.9563$:

    > I picked up a PSU yesterday as a replacement for an el-cheapo that
    > blew up under warranty. The one that blew was a "Leaf" brand, 400W.


    Have you ever considered investing in a good quality PSU? Sometimes it is
    better to pay closer to $100 than $40 for a quality PSU that will do the
    job for many years.


    --
    Mark Heyes (New Zealand)
    See my pics at http://homepages.ihug.co.nz/~markh/
    "There are 10 types of people, those that
    understand binary and those that don't"
     
    MarkH, Jul 11, 2004
    #6
  7. Matthew Poole

    steve Guest

    ~misfit~ wrote:

    > Ok, I'm not that electrically minded (so to speak) but isn't that +12v
    > figure a little low, considering it has "P4" in large letters on the side
    > and has the 12v four-pin CPU power connector? Considering the power draw
    > of a modern CPU, surely there wouldn't be much left of that 12A on the
    > +12v left for drives etc.


    Your drives would typically get power direct from the PSU...and not through
    a connector from the mobo......

    > Maybe I'm all wet on this one.
    > --
    > ~misfit~


    Maybe.....sounds like it. :)
     
    steve, Jul 11, 2004
    #7
  8. Matthew Poole

    steve Guest

    Harry wrote:

    > The CPU runs off the 3.3v.
    >
    > 3.3*26 + 5*30 + 12*12 + 12*0.5 + 5*0.8 +5*2 = 399.8 watts


    Harry

    Can you explain what you are adding up here?

    You've got me curious.
     
    steve, Jul 11, 2004
    #8
  9. Matthew Poole

    Enkidu Guest

    On Sun, 11 Jul 2004 19:32:00 +1200, steve <>
    wrote:

    >Harry wrote:
    >
    >> The CPU runs off the 3.3v.
    >>
    >> 3.3*26 + 5*30 + 12*12 + 12*0.5 + 5*0.8 +5*2 = 399.8 watts

    >
    >Harry
    >
    >Can you explain what you are adding up here?
    >
    >You've got me curious.


    From the OP:
    +3.3v 26A, +5v 30A, +12v 12A, -12v 0.5A, -5v
    0.8A, +5vsb 2A.

    He's calculating the (max) power from the max amperage x voltage.

    Cheers,

    Cliff
     
    Enkidu, Jul 11, 2004
    #9
  10. Matthew Poole

    colinco Guest

    In article <>, says...
    > Your drives would typically get power direct from the PSU...and not through
    > a connector from the mobo......
    >

    Doesn't matter where they get it, there's still only 12A. Typical early
    PSU design with 12V feed to CPUs but not enough of it and 5V to spare.
     
    colinco, Jul 11, 2004
    #10
  11. On Sun, 11 Jul 2004 03:20:35 GMT, (Matthew Poole) wrote:

    >In article <OT2Ic.9563$>, "~misfit~" <> wrote:
    >*SNIP*
    >>I've only just examined it a bit more closely. It's a "Texconn KY-5 00ATX
    >>400 WATT Power Supply" in large letters. Then, in *a lot* smaller letters
    >>below is has Output (Max): +3.3v 26A, +5v 30A, +12v 12A, -12v 0.5A, -5v
    >>0.8A, +5vsb 2A.
    >>
    >>Ok, I'm not that electrically minded (so to speak) but isn't that +12v
    >>figure a little low, considering it has "P4" in large letters on the side
    >>and has the 12v four-pin CPU power connector? Considering the power draw of
    >>a modern CPU, surely there wouldn't be much left of that 12A on the +12v
    >>left for drives etc.
    >>
    >>Maybe I'm all wet on this one.

    >
    >The drives all run off the 5V and 3.3V rails. Hence the high amp
    >ratings for those. The 12V stuff is just there for the CPU, so 12A is
    >heaps, even when feeding one of the latest monstrosities to come from
    >Intel.




    Bollocks the minimum Rated Intel Specs is 18A for the +12v supply, go do some
    reading and stop posting CRAP..

    And Drives all use +12V
     
    The GHOST of WOGER., Jul 11, 2004
    #11
  12. On Sun, 11 Jul 2004 16:05:15 +1200, Harry <> wrote:

    >~misfit~ wrote:
    >
    >> I picked up a PSU yesterday as a replacement for an el-cheapo that blew up
    >> under warranty. The one that blew was a "Leaf" brand, 400W. The shop took
    >> it out back, tested it, looked at my receipt, then gave me another, new,
    >> PSU. I galnced at it, saw it was a different brand but had "400 WATT" in
    >> large letters on the label and came home.
    >>
    >> I've only just examined it a bit more closely. It's a "Texconn KY-5 00ATX
    >> 400 WATT Power Supply" in large letters. Then, in *a lot* smaller letters
    >> below is has Output (Max): +3.3v 26A, +5v 30A, +12v 12A, -12v 0.5A, -5v
    >> 0.8A, +5vsb 2A.
    >>
    >> Ok, I'm not that electrically minded (so to speak) but isn't that +12v
    >> figure a little low, considering it has "P4" in large letters on the side
    >> and has the 12v four-pin CPU power connector? Considering the power draw
    >> of a modern CPU, surely there wouldn't be much left of that 12A on the
    >> +12v left for drives etc.
    >>
    >> Maybe I'm all wet on this one.

    >
    >The CPU runs off the 3.3v.
    >
    >3.3*26 + 5*30 + 12*12 + 12*0.5 + 5*0.8 +5*2 = 399.8 watts




    Gee another brain dead idiot, NO IT DOES NOT, all new CPU'use the +12v supply
     
    The GHOST of WOGER., Jul 11, 2004
    #12
  13. Matthew Poole

    ~misfit~ Guest

    Harry wrote:
    > ~misfit~ wrote:
    >
    >> I picked up a PSU yesterday as a replacement for an el-cheapo that
    >> blew up under warranty. The one that blew was a "Leaf" brand, 400W.
    >> The shop took it out back, tested it, looked at my receipt, then
    >> gave me another, new, PSU. I galnced at it, saw it was a different
    >> brand but had "400 WATT" in large letters on the label and came home.
    >>
    >> I've only just examined it a bit more closely. It's a "Texconn KY-5
    >> 00ATX 400 WATT Power Supply" in large letters. Then, in *a lot*
    >> smaller letters below is has Output (Max): +3.3v 26A, +5v 30A, +12v
    >> 12A, -12v 0.5A, -5v
    >> 0.8A, +5vsb 2A.
    >>
    >> Ok, I'm not that electrically minded (so to speak) but isn't that
    >> +12v figure a little low, considering it has "P4" in large letters
    >> on the side and has the 12v four-pin CPU power connector?
    >> Considering the power draw of a modern CPU, surely there wouldn't be
    >> much left of that 12A on the +12v left for drives etc.
    >>
    >> Maybe I'm all wet on this one.

    >
    > The CPU runs off the 3.3v.


    I was under the impression that, other than the 'new' boards that use the
    four-pin 12v plug for CPU power, the CPU ran off the +5v rail with the PCI
    and AGP devices (Graphics cards) mainly using the +3.3v rail.

    > 3.3*26 + 5*30 + 12*12 + 12*0.5 + 5*0.8 +5*2 = 399.8 watts


    Ok, thanks.
    --
    ~misfit~
     
    ~misfit~, Jul 11, 2004
    #13
  14. Matthew Poole

    ~misfit~ Guest

    MarkH wrote:
    > "~misfit~" <> wrote in
    > news:OT2Ic.9563$:
    >
    >> I picked up a PSU yesterday as a replacement for an el-cheapo that
    >> blew up under warranty. The one that blew was a "Leaf" brand, 400W.

    >
    > Have you ever considered investing in a good quality PSU? Sometimes
    > it is better to pay closer to $100 than $40 for a quality PSU that
    > will do the job for many years.


    Yeah, in my two main, higher powered machines I'm using ~$100 PSU's. I just
    have a bunch of older machines that I can't afford to spend that much on for
    PSU's.
    --
    ~misfit~
     
    ~misfit~, Jul 11, 2004
    #14
  15. Matthew Poole

    ~misfit~ Guest

    steve wrote:
    > ~misfit~ wrote:
    >
    >> Ok, I'm not that electrically minded (so to speak) but isn't that
    >> +12v figure a little low, considering it has "P4" in large letters
    >> on the side and has the 12v four-pin CPU power connector?
    >> Considering the power draw of a modern CPU, surely there wouldn't be
    >> much left of that 12A on the +12v left for drives etc.

    >
    > Your drives would typically get power direct from the PSU...and not
    > through a connector from the mobo......


    Yep, I realise that. However, the quoted 12A for the +12v rail isn't just
    for the mobo connector, it's for all 12v connections including the molex
    connectors for the drives.

    Cheers,
    --
    ~misfit~
     
    ~misfit~, Jul 11, 2004
    #15
  16. On Sun, 11 Jul 2004 22:13:00 +1200, "~misfit~" <>
    wrote:

    >steve wrote:
    >> ~misfit~ wrote:
    >>
    >>> Ok, I'm not that electrically minded (so to speak) but isn't that
    >>> +12v figure a little low, considering it has "P4" in large letters
    >>> on the side and has the 12v four-pin CPU power connector?
    >>> Considering the power draw of a modern CPU, surely there wouldn't be
    >>> much left of that 12A on the +12v left for drives etc.

    >>
    >> Your drives would typically get power direct from the PSU...and not
    >> through a connector from the mobo......

    >
    >Yep, I realise that. However, the quoted 12A for the +12v rail isn't just
    >for the mobo connector, it's for all 12v connections including the molex
    >connectors for the drives.
    >
    >Cheers,




    If the PSU does not meet the ATX 12V V1.2 then its utter Crap..

    18A is the rating..

    Cheap PSU have no output over voltage protection and can fry your Total PC,
    every thing gets blown..

    And of course no input over voltage protection..



    You get what you pay for..
     
    The GHOST of WOGER., Jul 11, 2004
    #16
  17. Matthew Poole

    steve Guest

    Enkidu wrote:

    > On Sun, 11 Jul 2004 19:32:00 +1200, steve <>
    > wrote:
    >
    >>Harry wrote:
    >>
    >>> The CPU runs off the 3.3v.
    >>>
    >>> 3.3*26 + 5*30 + 12*12 + 12*0.5 + 5*0.8 +5*2 = 399.8 watts

    >>
    >>Harry
    >>
    >>Can you explain what you are adding up here?
    >>
    >>You've got me curious.

    >
    > From the OP:
    > +3.3v 26A, +5v 30A, +12v 12A, -12v 0.5A, -5v
    > 0.8A, +5vsb 2A.
    >
    > He's calculating the (max) power from the max amperage x voltage.
    >
    > Cheers,
    >
    > Cliff


    I get the drift.....but it exposes the how I REALLY need to learn more about
    electricity. I've been putting that one off too long. Looks like it's now
    very much overdue.
     
    steve, Jul 11, 2004
    #17
  18. Matthew Poole

    steve Guest

    ~misfit~ wrote:

    > steve wrote:
    >> ~misfit~ wrote:
    >>
    >>> Ok, I'm not that electrically minded (so to speak) but isn't that
    >>> +12v figure a little low, considering it has "P4" in large letters
    >>> on the side and has the 12v four-pin CPU power connector?
    >>> Considering the power draw of a modern CPU, surely there wouldn't be
    >>> much left of that 12A on the +12v left for drives etc.

    >>
    >> Your drives would typically get power direct from the PSU...and not
    >> through a connector from the mobo......

    >
    > Yep, I realise that. However, the quoted 12A for the +12v rail isn't just
    > for the mobo connector, it's for all 12v connections including the molex
    > connectors for the drives.
    >
    > Cheers,
    > --
    > ~misfit~


    OK....Thanks.

    That makes it clearer for ME. :)

    I had assumed - wrongly it seems - that a PSU could provide more variation
    than that.
     
    steve, Jul 11, 2004
    #18
  19. Matthew Poole

    GraB Guest

    On Sun, 11 Jul 2004 06:59:13 +0000 (UTC), MarkH <>
    wrote:

    >"~misfit~" <> wrote in
    >news:OT2Ic.9563$:
    >
    >> I picked up a PSU yesterday as a replacement for an el-cheapo that
    >> blew up under warranty. The one that blew was a "Leaf" brand, 400W.

    >
    >Have you ever considered investing in a good quality PSU? Sometimes it is
    >better to pay closer to $100 than $40 for a quality PSU that will do the
    >job for many years.


    Some manufacturers have the combined wattage of the +3.3v and +5v
    rails, which, I understand, is more important than the overall rating
    of the PSU. That combined figure on my 250W PSU is 150W. I had a
    look at some cheap PSUs in a Dunedin supplier that were rated as 300W
    but the combined figure for those was only 130W, less than my 250W
    PSU.
     
    GraB, Jul 11, 2004
    #19
  20. Matthew Poole

    colinco Guest

    In article <>,
    says...
    > Some manufacturers have the combined wattage of the +3.3v and +5v
    > rails, which, I understand, is more important than the overall rating
    > of the PSU.
    >

    Only if you use +5V for a major load.
     
    colinco, Jul 11, 2004
    #20
    1. Advertising

Want to reply to this thread or ask your own question?

It takes just 2 minutes to sign up (and it's free!). Just click the sign up button to choose a username and then you can ask your own questions on the forum.
Similar Threads
  1. Linønut

    What about COLA lately, huh?

    Linønut, Jan 30, 2005, in forum: Computer Support
    Replies:
    1
    Views:
    447
    Warrior
    Jan 30, 2005
  2. [blu|shark]

    EOS 300 DOF preview? huh?

    [blu|shark], Jan 15, 2004, in forum: Digital Photography
    Replies:
    6
    Views:
    682
    Tony Spadaro
    Jan 15, 2004
  3. The Intrinsically Flawed Mr. Hole

    "Forgotten Silver" released today at Netflix. Huh?

    The Intrinsically Flawed Mr. Hole, Oct 27, 2004, in forum: DVD Video
    Replies:
    2
    Views:
    538
    The Intrinsically Flawed Mr. Hole
    Oct 27, 2004
  4. Tobamore

    sshdrv in device manager - huh?

    Tobamore, Jul 13, 2004, in forum: Computer Security
    Replies:
    1
    Views:
    455
    johns
    Jul 13, 2004
  5. BD[MCNGP]
    Replies:
    13
    Views:
    604
    Kline Sphere
    Feb 9, 2007
Loading...

Share This Page