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+12v rail

guys, what is the difference between single rail +12v@45A and triple rail +12v@15A.
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  1. Single +12V>= Triple +12V rail.

    Simply buy a single rail PSU ....
  2. shubham1401 said:
    Single +12V>= Triple +12V rail.

    Simply buy a single rail PSU ....

    sorry friend, i think u don't understand my question. i didn't ask for buying psu. i ask for explanation. how single rail +12v with big amp would be good than the triple rail with the same amp. what is the role of a rail if the rails devided by 2 or 3?
  3. yus_29 said:
    guys, what is the difference between single rail +12v@45A and triple rail +12v@15A.

    Most 12v multi-rail units can't output what they add up to.
    For most computer user's the difference between multi-rail and single-rail is meaningless, but 3 x 15a @ 12v is rather crappy, I'd go with the single 45a rail in that scenario.

    Before anyone comes in and say's " most psu's are single rail anyway ";
    Multi-rail designs ( other than those 1000watt or higher ) are fed from a single 12v source that is divided useing OCP ( Over Current Protection circuits ).
    In most cases those protections are set higher than the stated rating, example;
    750 watt Antec TPN ( currently powering my system ) has 4 x 25a @ 12v on the label ( 62a combined ), by going to the Antec site you will find that the OCP is actually set for 40a per rail ( most unit's are not set this much higher ).

    I've also run the same system with a
    3 x 18a unit ( Corsair 620HX/ max load 50a, considered to be single rail because of a high or non existing OCP setting )
    4 x 20a unit ( TPN550/ max load 45a )
    4 x 18a unit ( Odin GT550/ max load 41a )
    2 x 17a unit ( Antec EA500S max load 34a, again considered as a single rail unit due to high OCP setting )

    You'll notice that the EA 500 goes against what I said above, by being able to ouput the sum of it's rails, it's the one exception that I know of. It's the earlier Seasonic built design, the new revision is Delta built with 2 x 22a / max load 34a ( OCP set at 25a )


    Overall, if you're not building a multi gpu super gamer it is more important to worry about quality than number of rails.

    I see that obsidian has already thrown in the link, read it.
  4. My Antec 650 watt TP3 label says three 19 amp rails with a total of 52 amps.
  5. jsc said:
    My Antec 650 watt TP3 label says three 19 amp rails with a total of 52 amps.

    Another Seasonic build with no OCP.
  6. thanks for the link obsidian. very detail answer. the bottom line is, split rail is better right? thanks.
  7. better in some cases worse in others
  8. yeah, worse for serious super gamers but in my rig, i think it is best for having split rail.
  9. delluser1 said:
    Another Seasonic build with no OCP.

    That's one reason why I'm gradually moving to Corsair. I still have a 550 watt TP3 in a system.

    But I have moved the 650 watt PSU to my test/spares bin.
  10. Best answer
    yus_29 said:
    thanks for the link obsidian. very detail answer. the bottom line is, split rail is better right? thanks.

    The bottom line is that in most cases, split vs single rail makes no difference. Look for quality, not rail count.
  11. jsc said:
    That's one reason why I'm gradually moving to Corsair. I still have a 550 watt TP3 in a system.

    But I have moved the 650 watt PSU to my test/spares bin.


    The original Corsair HX series ( 520,620 ) are the same, high or non existing OCP.
    My TP3 650 sits in a server
    And my spares
  12. is that a real cwt in the middle where is that from
  13. Number 2 from the top ?
    It's a CWT , they were supposed to send the Gold rated version but some warehouse worker messed up and sent the Silver instead.
    Only 1.25% difference in eff. so not worth the hassle of returning it.
  14. didn know you can buy a cwt oem
  15. shhhh, it's a secret.
  16. hmmm i wonder
  17. Nothing like a well equipped spare parts bin.
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