Announcement

Collapse
No announcement yet.

msi B250M PRO-VH

Collapse
X
 
  • Filter
  • Time
  • Show
Clear All
new posts

    msi B250M PRO-VH

    hi
    i have a problem with this board:
    msi B250M PRO-VH
    when i press power button, nothing happens, the jumper of the power button has 3v.
    the board works normally by joining the green wire with the black one.
    i tried to short the power crystal but with no success.
    also reflashed the bios...
    Last edited by mazloum; 09-12-2021, 06:05 AM.

    #2
    Re: msi B250M PRO-VH

    even if i reset the cmos, it will not power up by itself

    Comment


      #3
      Re: msi B250M PRO-VH

      This is a motherboard start up circuit issue. there are many possibilities due to this. you must trace to SIO to see if it send signal to PCH. etc.. not so simple

      Comment


        #4
        Re: msi B250M PRO-VH

        1. Take the schematics, it's here: https://www.badcaps.net/forum/showthread.php?p=1070801
        Try to study the power sequence diagram, what happens when Power Button is pushed (before and after), and what signals are involved.

        2. Find and download the SiO datasheet for pinout and try to understand what SiO does on PowerButton push, check all the supply voltages, also the voltages monitored by the SiO (VIN signals).

        3. Look for what is happening on the SIO with signals like Power Button, SLP_S3# (usually wakes several VRMs, an output of the chipset, which follows SIO signal to chipset), PSIN#/PSON#, power good signals.

        4. Check if Power Button signal arrives at the SIO, check if PSON# from SIO arrives at ATX PSU connector.

        5. Some Motherboards/SIO's also do monitor CPU present signal, and HOT_PROC signal.

        6. Go sure that your PSU is OK (check if 5V_VSB is present when powered off), go sure CPU is OK (check on different board). Sometimes very silly things prevent a device to work, as humans tend to assume the worst thing did happen, we often disregard the obvious things.

        7. Check the board for cutted tracks and ripped off components.

        8. Getting a boardview also can help a lot.

        The problem should be somewhere between the power button, via the SIO until the chipset, as if you force the PSU to run the board works.
        From my experience often the SIO's and chipsets fail, eg due to a power spike, they can also fail partially, so that a particular signal does not work. So you can also do the brute force method beginning with exchanging SIO, then the chipset (exchanging the chipset is not easy as this is a BGA device, this is usually the last choice, unless the chipset is shorted on the power supply signals - can be measured on the caps of the chipset, inside is always +, outside GND).
        Last edited by DynaxSC; 03-29-2022, 07:59 AM.

        Comment


          #5
          Re: msi B250M PRO-VH

          Forgot to write, SLP_S3# enables also the PSON# via the SIO. Chipset also monitors the Power Button signal, and probably based also on that generates the SLP_S3# signal.

          Comment


            #6
            Re: msi B250M PRO-VH

            Make sure the battery is 3.3V

            Comment

            Working...
            X