Vcore tolerance

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  • Tocken
    New Member
    • May 2006
    • 2
    #1

    Vcore tolerance

    Hello all, here's a question from a newbie:

    The Vcore (1,5V) was very noisy (~0,5Vpp) on a 3-year-old Jetway MB (P4/2,6GHz), so I replaced 9x leaky GSC 1500uF/6,3V with 8x2200uF/6,3V.

    With the new caps, there are still some noise <0,1Vpp.
    The frequence of noise seems to increase when moving the mouse but the system feels much more stable now (no more freezes).

    Anyone knows the tolerance of Vcore noise on a P4?

    (sorry for my bad English)
    Tags: None
    • Per Hansson
      Super Moderator
      • Jul 2005
      • 5895
      • Sweden
      #2
      Re: Vcore tolerance

      No idea, but check out the PSU too, you could also have badcaps on the +12v line...
      "The one who says it cannot be done should never interrupt the one who is doing it."

        Comment

        • linuxguru
          Badcaps Legend
          • Apr 2005
          • 1564
          #3
          Re: Vcore tolerance

          What brand and series are the new 2200/6.3 caps? These have to be ultra-low ESR for the P4 Vcore rail. Recommended series are Rubycon MBZ/MCZ, Nichicon HZ, NCC KZG and Samxon GA (?).

            Comment

            • Brian C
              Senior Member
              • Dec 2006
              • 156
              #4
              Re: Vcore tolerance

              I would like to see the voltage waveform ... if u have.

                Comment

                • Fizzycapola
                  Badcaps Veteran
                  • Oct 2006
                  • 423
                  #5
                  Re: Vcore tolerance

                  0.1v fluctuation doesn't sound anything to be concerned about, I can remember all my brand new PC's mine and friends having around this ammount of fluctuation, if you used general grade capacitors, you may get it down to 0.05v perhaps with better caps.
                  Rubycon Rubycon Rubycon

                    Comment

                    • Tocken
                      New Member
                      • May 2006
                      • 2
                      #6
                      Re: Vcore tolerance

                      Sorry for my late reply...

                      linuxguru:
                      The new capacitors are Sanyo MV-WX 105°C.


                      Brian C:
                      Sorry but I used an old crt-scope and it's a little tricky to take snapshots of the waveform with my digital camera...
                      btw, the computer works fine now.

                      Thanks for your help, all of you.

                        Comment

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