-12v & -5v question

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  • uligli
    Senior Member
    • Aug 2006
    • 139

    #1

    -12v & -5v question

    It's a problem that -5v is at -0.78v?

    I recapped the PSU three months ago, 3 small ones and 2 2000uF+ caps, it's been working fine then. Today i saw the -12v & -5v rails, and i'm worried, will be a problem those voltages?
    Attached Files
  • uligli
    Senior Member
    • Aug 2006
    • 139

    #2
    Re: -12v & -5v question

    The PSU is a Hyper TypeR 580w, bought it in 2006.
    My pc config:
    Opteron 144 oc 2.7g
    DFI nForce4 UltraD
    1G ddr ram
    X1950pro (replaced by 7300GT last week after i burned it accidentally)

    Comment

    • Per Hansson
      Super Moderator
      • Jul 2005
      • 5895
      • Sweden

      #3
      Re: -12v & -5v question

      That would be out of spec (the standard calls for +/- 10%) however nowdays -5v has been removed from spec and -12v is only used for legacy stuff

      So it is likely your board does not load the rails at all and then they may be way off
      Also mainboard readings are usually also way off the mark, to know you have to use a multimeter...

      This thread has more info about the usages for -5v and -12v
      https://www.badcaps.net/forum/showthread.php?t=9894
      "The one who says it cannot be done should never interrupt the one who is doing it."

      Comment

      • POM_MJ
        Badcaps Veteran
        • Aug 2009
        • 228

        #4
        Re: -12v & -5v question

        Firstly, check if your PSU have a white wire to supply -5V output.
        recently PSU don't have it anymore.

        however, DFI NF4 Ultra-D don't need -5V.
        | AMD Phenom II X2 550BE | GIGABYTE GA-MA790FXT-UD5P | GeIL DDR3 Ultra 2x2GB 1600C7 |
        | XFX GTS250 DDR3 512MB | Dell H525EF-00 | Lancool PC-K62 Black | Samsung 2232GW |
        | 2xWD7500AYYS | 2xHD322GJ Raid0 |

        Comment

        • kc8adu
          Super Moderator
          • Nov 2003
          • 8832
          • U.S.A!

          #5
          Re: -12v & -5v question

          measure with dvm to be sure.
          50/50 psu or misreported voltage.
          type r for ricer?
          sounds like a cheapie.

          Comment

          • mur
            Member
            • Feb 2010
            • 21

            #6
            Re: -12v & -5v question

            Either the psu doesn't have -5v rail or mobo reading is false.

            Either way you can't trust motherboard readings. My board reports my 12V rail at 4.86V, 3.3V at 1.15V and -12V at -3.97V. Only the 5V reading seems fine at 5.03V.

            Comment

            • Pyr0Beast
              Badcaps Veteran
              • Feb 2009
              • 406

              #7
              Re: -12v & -5v question

              Heh. If negative rails were that high I'm pretty sure PSU would turn itself off.

              Comment

              • uligli
                Senior Member
                • Aug 2006
                • 139

                #8
                Re: -12v & -5v question

                Thanks a lot guys for the replies make me the things clear

                Actually the serial ports and FDD are disable, may be that's why readings are low.

                Comment

                • uligli
                  Senior Member
                  • Aug 2006
                  • 139

                  #9
                  Re: -12v & -5v question

                  Originally posted by kc8adu
                  measure with dvm to be sure.
                  50/50 psu or misreported voltage.
                  type r for ricer?
                  sounds like a cheapie.
                  Well. cost me $99 in 2006, not a cheapie at all, was one of the most expensive PSUs, i think it was one of the first modular PSUs at that time.
                  Attached Files

                  Comment

                  • Per Hansson
                    Super Moderator
                    • Jul 2005
                    • 5895
                    • Sweden

                    #10
                    Re: -12v & -5v question

                    Did you replace all the Fuhjyyu capacitors?
                    "The one who says it cannot be done should never interrupt the one who is doing it."

                    Comment

                    • Pyr0Beast
                      Badcaps Veteran
                      • Feb 2009
                      • 406

                      #11
                      Re: -12v & -5v question

                      Sorry to say this. But this is a piece of overpriced garbage.
                      Replace ones on -12 and -5V lines as well, but those are not used for anything today but the COM port drivers.
                      Those on 5V are bloated, replace them ASAP if you didn't already.

                      Comment

                      • 370forlife
                        Large Marge
                        • Aug 2008
                        • 3112
                        • United States

                        #12
                        Re: -12v & -5v question

                        That hiper isn't so much of a cheapie. It's from 2006, a bit more of a 5v/3.3v heavy unit but this was a early one with modular and a 120mm fan, it was $99 back then for a reason. Other than the caps, it's a pretty good performing andyson build. Voltage regulation is OK, but the ripple is very well controlled.


                        http://www.jonnyguru.com/modules.php...Story2&reid=16

                        Comment

                        • Pyr0Beast
                          Badcaps Veteran
                          • Feb 2009
                          • 406

                          #13
                          Re: -12v & -5v question

                          I'd place it under same tag as a tagan. Fuhyyu caps ruin them all and recap is costly and very time consuming.

                          Comment

                          • uligli
                            Senior Member
                            • Aug 2006
                            • 139

                            #14
                            Re: -12v & -5v question

                            Originally posted by Per Hansson
                            Did you replace all the Fuhjyyu capacitors?
                            Not all of them, couldn't find the big ones, anyway it's working fine, next time i will recap them all, because is a pain to dismantle the modular conectors.

                            Comment

                            • momaka
                              master hoarder
                              • May 2008
                              • 12175
                              • Bulgaria

                              #15
                              Re: -12v & -5v question

                              Originally posted by uligli
                              Not all of them, couldn't find the big ones, anyway it's working fine, next time i will recap them all, because is a pain to dismantle the modular conectors.
                              It's okay if you didn't replace the primary 200v caps, since they rarely go bad. However, it looks like there are some others that you might need to. Take a look in the picture I've attached below - the caps circled in green filter the 5vsb, and they seem bulged. Definitely replace them if they are.
                              Also, I think this PSU has 2-transistor 5vsb design as well - in such design, there is one small cap that is critical to the regulation of the 5vsb - when it goes bad the 5vsb can get as high as 12v and kill the motherboard. The cap circled in red (22uF, 50v?) seems to match the specs of what is usually used for those critical caps. Get a low ESR cap from a good brand to replace it. Stick with the same exact specs as the original one.
                              Attached Files

                              Comment

                              • uligli
                                Senior Member
                                • Aug 2006
                                • 139

                                #16
                                Re: -12v & -5v question

                                Thanks momaka for the advices, the bulged caps have already recapped, thoses pics were taken before the recap. I will replace the cap in the red circle.

                                Comment

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