Howdy, Stranger!

It looks like you're new here. If you want to get involved, click one of these buttons!

12 pin CPU aux power plug

GladDogGladDog Member RarePosts: 1,097
edited April 2021 in Hardware
With Intel dropping prices on 10 gen CPUs, I took advantage and bought one, an 17-10700F.  I also bought a motherboard & 64GB DDR4-3200 RAM.  The rest of the stuff is good to go; pair of 1TB SSDs, an Intel 660p & a Crucial SATA III M2, and I just bought a new gamer RGB case with glass side of course, and 750W PSU about 3 months ago, so there won't be anything older than 3 months other than the SATA III SSD and the Win10 copy.  Also, wanted to get a new GPU, but Fugedaboutit.  I'll stay with my EVGA RTX2060 KO 6GB until GPU prices settle down.  I'm playing at 2560x1080, so the card is plenty for now.

So on to my problem.  I was happily assembling my rig when I noted a problem that I am not sure of the solution.  The motherboard CPU aux fan plug needs either an 8 + 4 or a 4 + 4 + 4 insert.  All the PSU has is a 4 + 4.  My question is; can I use an 8 pin PCIe power plug you would normally use on a GPU card?  The insert fits fine, but I want to be sure before I pump a potential 150W death sentence into my shiny new motherboard and CPU.  Yes, I sent the same question to the motherboard manufacturer, but I am not expecting a reply until Monday.


The world is going to the dogs, which is just how I planned it!


Comments

  • QuizzicalQuizzical Member LegendaryPosts: 25,499
    What motherboard do you have?  I've never heard of a 12-pin CPU power connector.  Even the Z590 motherboards for Rocket Lake only need an 8-pin connector.
  • GladDogGladDog Member RarePosts: 1,097
    edited April 2021
    Its an Asrock Steel Legend H470.  ASRock H470 STEEL LEGEND LGA 1200 ATX Intel Motherboard - Newegg.com

    Btw, it is well rated on other sites, something I found after only seeing a single rating on Newegg.


    The world is going to the dogs, which is just how I planned it!


  • GladDogGladDog Member RarePosts: 1,097
    Do you think I would be fine with just using the 8 pin plug?  I bought the 65W version, not the 125W version.


    The world is going to the dogs, which is just how I planned it!


  • QuizzicalQuizzical Member LegendaryPosts: 25,499
    I'd look closely at the shape of the pins, or more to the point, the plastic sheathes that protect them.  Some of them are square, and others have two corners rounded off.  This ensures that you can't put in a connector backwards.  The combination of which particular "pins" are square rather than rounded is different for an 8-pin CPU power connector from an 8-pin PCI-E power connector.  This makes it so that you can't use them in the wrong spot, as they won't physically fit.

    From looking at some spare connectors, with an O for a rounded connector and an X for a square one, PCI Express looks like this:

    OOOX
    XXOO

    8-pin CPU connector looks like this:

    OOOX
    OOXO

    That will allow you to see if the motherboard's 8-pin connector requires a standard CPU connector or PCI Express, as the other of the two won't physically fit.
  • Asm0deusAsm0deus Member EpicPosts: 4,618
    edited April 2021
    You should be fine just plugging in the standard 8pin cpu connector.  It's a newish thing to have an extra 4pin connector to supply another 12v current to the mobo for extrme OC etc

    In most cases you do not need to plug it in, it shouldn't hurt anything whether you plug it in or not.

    Brenics ~ Just to point out I do believe Chris Roberts is going down as the man who cheated backers and took down crowdfunding for gaming.





  • HyperpsycrowHyperpsycrow Member RarePosts: 954
    i dont understand the problem..mobo usualy has 12 pin power in the side and a 8 pin in the upper corner, then there is sockets with 3 pins for fans to the case and the cpu and so i dont know why ur psu dont have these power plugs or fans




  • GladDogGladDog Member RarePosts: 1,097
    i dont understand the problem..mobo usualy has 12 pin power in the side and a 8 pin in the upper corner, then there is sockets with 3 pins for fans to the case and the cpu and so i dont know why ur psu dont have these power plugs or fans
    There is a 20+4 pin main board connector, and where I was expecting to see an 8 pin connector at the upper left, there is a 12 pin connector.  The PSU has an 8 pin connector for CPU aux power, which is what I was looking for.


    The world is going to the dogs, which is just how I planned it!


  • Asm0deusAsm0deus Member EpicPosts: 4,618
    edited April 2021
    GladDog said:
    i dont understand the problem..mobo usualy has 12 pin power in the side and a 8 pin in the upper corner, then there is sockets with 3 pins for fans to the case and the cpu and so i dont know why ur psu dont have these power plugs or fans
    There is a 20+4 pin main board connector, and where I was expecting to see an 8 pin connector at the upper left, there is a 12 pin connector.  The PSU has an 8 pin connector for CPU aux power, which is what I was looking for.

    Top left here yes?




    You plug in the 24 atx connector and the 8 pin connector on the top left if you are able plug in the extra 4pins if not don't.

    It's there for extra power just in case but not needed.

    GladDog[Deleted User]

    Brenics ~ Just to point out I do believe Chris Roberts is going down as the man who cheated backers and took down crowdfunding for gaming.





  • GladDogGladDog Member RarePosts: 1,097
    Asm0deus said:
    You should be fine just plugging in the standard 8pin cpu connector.  It's a newish thing to have an extra 4pin connector to supply another 12v current to the mobo for extrme OC etc

    In most cases you do not need to plug it in, it shouldn't hurt anything whether you plug it in or not.
    Quite honestly, I was planning on trying it with just the 8 pin plug filled, but there is a lot of hardware know-how on this site, so I thought I would ask and see if anyone had any insight.


    The world is going to the dogs, which is just how I planned it!


  • QuizzicalQuizzical Member LegendaryPosts: 25,499
    GladDog said:
    Its an Asrock Steel Legend H470.  ASRock H470 STEEL LEGEND LGA 1200 ATX Intel Motherboard - Newegg.com

    Btw, it is well rated on other sites, something I found after only seeing a single rating on Newegg.
    That's not a single 12-pin connector.  That's an 8-pin connector and another 4-pin connector next to it.  Some power supplies come with two CPU power connectors, and it looks like that motherboard wants you to use both of them.  It really shouldn't be necessary, but Comet Lake is quite the power hog.

    You should be warned that TDP for CPUs really isn't meaningful anymore.  Even at stock settings, Intel feels free to have their processors use vastly more power than the TDP.  Or perhaps rather, Intel creates some "recommended" settings and then encourages motherboard vendors to ignore then and use a lot more power so that they can get higher performance.  Comet Lake will probably stay inside of a PL2 power of 250 W, though Rocket Lake sometimes doesn't.

    A Core i7-10700F will probably use less power than the higher bins, but I'm not really sure how much less power.  You should also be warned that power used is equal to heat output (by conservation of energy), and sticking a cheap air cooler on a Comet Lake CPU might result in woefully insufficient cooling.  It might be okay on the particular CPU that you have even if it wouldn't on one of the higher bins, but Intel didn't send them out for review, so we don't know.  With recent AMD CPUs, you know that it's going to stay inside of 142 W apart from manual overclocking, but recent Intel CPUs don't really have any analogous guarantees.
    GladDog[Deleted User]
  • Asm0deusAsm0deus Member EpicPosts: 4,618
    Again unless doing some extreme OCing the extra 4 pin isn't needed.
    GladDog

    Brenics ~ Just to point out I do believe Chris Roberts is going down as the man who cheated backers and took down crowdfunding for gaming.





  • GladDogGladDog Member RarePosts: 1,097
    Thanks for the tip Quizz, I learned my lesson decades ago about going cheap on cooling.  The cooler I bought for this is well rated and has about 3X the material in teh heat sink as what is stock, as well as having a 120mm fan.  If thats not enough, I have an 8 year old liquid cooler I can use until I can get a more modern one.


    The world is going to the dogs, which is just how I planned it!


  • GladDogGladDog Member RarePosts: 1,097
    edited April 2021
    Asm0deus said:
    GladDog said:
    i dont understand the problem..mobo usualy has 12 pin power in the side and a 8 pin in the upper corner, then there is sockets with 3 pins for fans to the case and the cpu and so i dont know why ur psu dont have these power plugs or fans
    There is a 20+4 pin main board connector, and where I was expecting to see an 8 pin connector at the upper left, there is a 12 pin connector.  The PSU has an 8 pin connector for CPU aux power, which is what I was looking for.

    Top left here yes?




    You plug in the 24 atx connector and the 8 pin connector on the top left if you are able plug in the extra 4pins if not don't.

    It's there for extra power just in case but not needed.

    That's it!


    The world is going to the dogs, which is just how I planned it!


  • GladDogGladDog Member RarePosts: 1,097
    Quizzical said:
    I'd look closely at the shape of the pins, or more to the point, the plastic sheathes that protect them.  Some of them are square, and others have two corners rounded off.  This ensures that you can't put in a connector backwards.  The combination of which particular "pins" are square rather than rounded is different for an 8-pin CPU power connector from an 8-pin PCI-E power connector.  This makes it so that you can't use them in the wrong spot, as they won't physically fit.

    From looking at some spare connectors, with an O for a rounded connector and an X for a square one, PCI Express looks like this:

    OOOX
    XXOO

    8-pin CPU connector looks like this:

    OOOX
    OOXO

    That will allow you to see if the motherboard's 8-pin connector requires a standard CPU connector or PCI Express, as the other of the two won't physically fit.
    The pattern for this plug is;

    OXXO
    XOOX

    Wierd


    The world is going to the dogs, which is just how I planned it!


  • Asm0deusAsm0deus Member EpicPosts: 4,618
    edited April 2021
    GladDog said:
    Asm0deus said:
    GladDog said:
    i dont understand the problem..mobo usualy has 12 pin power in the side and a 8 pin in the upper corner, then there is sockets with 3 pins for fans to the case and the cpu and so i dont know why ur psu dont have these power plugs or fans
    There is a 20+4 pin main board connector, and where I was expecting to see an 8 pin connector at the upper left, there is a 12 pin connector.  The PSU has an 8 pin connector for CPU aux power, which is what I was looking for.

    Top left here yes?




    You plug in the 24 atx connector and the 8 pin connector on the top left if you are able plug in the extra 4pins if not don't.

    It's there for extra power just in case but not needed.

    That's it!

    Expect to see this on most newer mobo's, can't say in the future but right now most use cases it wont be needed. It just supplies an extra 12v current to the mobo.

    GamerNexus and der8bauer commented quite a bit on this too last year or so as it comes up often.

    As an ex repair tech I suggest plug it in if you can and if not do not worry about it too much unless you are doing some LN2 overclocking.

    Just a fyi I have a new ryzen 5800x in x570 tomahawk wifi and only have the  24pin and 8pin connectors plugged in, I left the extra 4pin connector empty.
    GladDog

    Brenics ~ Just to point out I do believe Chris Roberts is going down as the man who cheated backers and took down crowdfunding for gaming.





  • HyperpsycrowHyperpsycrow Member RarePosts: 954
    I never seen 8 + 4 sockets on mobos..most be for extra power but not needet unless you plan to run ur towns power suply :D




  • QuizzicalQuizzical Member LegendaryPosts: 25,499
    Asm0deus said:

    Just a fyi I have a new ryzen 5800x in x570 tomahawk wifi and only have the  24pin and 8pin connectors plugged in, I left the extra 4pin connector empty.
    Your CPU will reliably have power consumption stay inside of 142 W at stock settings.  The original poster's might not.  His has a PL2 power of 224 W, meaning that it's allowed to use up to that much in some circumstances.
  • Asm0deusAsm0deus Member EpicPosts: 4,618
    edited April 2021
    Quizzical said:
    Asm0deus said:

    Just a fyi I have a new ryzen 5800x in x570 tomahawk wifi and only have the  24pin and 8pin connectors plugged in, I left the extra 4pin connector empty.
    Your CPU will reliably have power consumption stay inside of 142 W at stock settings.  The original poster's might not.  His has a PL2 power of 224 W, meaning that it's allowed to use up to that much in some circumstances.

    Look it up and get back to me ;) 

    The extra 4 pin is simply for extra power stability when OCing. 

    Here's a hint with a 750w PSU I will eat my shorts if it doesn't do 12v 240w on the 8 pin itself easy.  The extra 4 pin is simply to provide more stability in case of spike's on extreme OC's.


    Better yet.


    Top of page 24 of the mobo manual:

    24ATX 12V Power Connector(4-pin ATX12V2)(see p.7, No. 34)
    Connecting an ATX 12V 4-pin cable here is optional.*The power supply plug fits into this connector in only one orientation

    At OP do not plug a PCIe PSU cable in here or in the 4pin connector only suppose to plug cables specified for the CPU in here.
    Post edited by Asm0deus on

    Brenics ~ Just to point out I do believe Chris Roberts is going down as the man who cheated backers and took down crowdfunding for gaming.





  • QuizzicalQuizzical Member LegendaryPosts: 25,499
    Asm0deus said:
    Quizzical said:
    Asm0deus said:

    Just a fyi I have a new ryzen 5800x in x570 tomahawk wifi and only have the  24pin and 8pin connectors plugged in, I left the extra 4pin connector empty.
    Your CPU will reliably have power consumption stay inside of 142 W at stock settings.  The original poster's might not.  His has a PL2 power of 224 W, meaning that it's allowed to use up to that much in some circumstances.

    Look it up and get back to me ;) 

    The extra 4 pin is simply for extra power stability when OCing. 

    Here's a hint with a 750w PSU I will eat my shorts if it doesn't do 12v 240w on the 8 pin itself easy.  The extra 4 pin is simply to provide more stability in case of spike's on extreme OC's.
    I would certainly expect that it should be fine with just the 8-pin connector.  An 8-pin PCI-E power connector is rated at 150 W, but no one seems to know what the CPU power connector is rated at, or if there even is a nominal specification.
  • Asm0deusAsm0deus Member EpicPosts: 4,618
    edited April 2021
    Quizzical said:
    Asm0deus said:
    Quizzical said:
    Asm0deus said:

    Just a fyi I have a new ryzen 5800x in x570 tomahawk wifi and only have the  24pin and 8pin connectors plugged in, I left the extra 4pin connector empty.
    Your CPU will reliably have power consumption stay inside of 142 W at stock settings.  The original poster's might not.  His has a PL2 power of 224 W, meaning that it's allowed to use up to that much in some circumstances.

    Look it up and get back to me ;) 

    The extra 4 pin is simply for extra power stability when OCing. 

    Here's a hint with a 750w PSU I will eat my shorts if it doesn't do 12v 240w on the 8 pin itself easy.  The extra 4 pin is simply to provide more stability in case of spike's on extreme OC's.
    I would certainly expect that it should be fine with just the 8-pin connector.  An 8-pin PCI-E power connector is rated at 150 W, but no one seems to know what the CPU power connector is rated at, or if there even is a nominal specification.

    CPU 8pin is higher which is why the plug pin outs are different.  Did you read the manual?

    btw a 8pin EPS connector which is what the cpu connectors are should be rated for like 235w continuous power with the 4 pin adding another 150ish for stability if needed at all.




    Post edited by Asm0deus on

    Brenics ~ Just to point out I do believe Chris Roberts is going down as the man who cheated backers and took down crowdfunding for gaming.





  • GladDogGladDog Member RarePosts: 1,097
    The manual was quite vague.  I used the 8 pin section and left the 4 pin empty, and it is running fine.  If there are errors in the future, I will get a new PSU with a 12 pin.


    The world is going to the dogs, which is just how I planned it!


  • QuizzicalQuizzical Member LegendaryPosts: 25,499
    GladDog said:
    The manual was quite vague.  I used the 8 pin section and left the 4 pin empty, and it is running fine.  If there are errors in the future, I will get a new PSU with a 12 pin.
    There is no such thing as a power supply with a 12-pin CPU power connector.  Some power supplies have two CPU power connectors, likely both 4+4 pin.  If yours does, then you might as well use the second connector on the 4-pin slot.  If it doesn't, then it's not likely to matter.
Sign In or Register to comment.