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Need help in repairing a dead motherboard

stealthjoe

New Member
Hello,

I have a Pentium 3 motherboard (iWill VA133plus) and yesterday I took it out from storage to test a processor. However, the board does not power on. Normally, the standby LED is illuminated when the PSU is connected. In my case, the LED is still off despite connected to the PSU in ON state. So due to this, I am unable to boot/post the motherboard. The voltages across the MOSFETs are also zero as the motherboard is not receiving any power.

Attached below are the images of the board specifically around the ATX connector. Could someone please share their experience with such an issue and the troubleshooting steps? Thanks.
 

Attachments

  • ATX 1.jpeg
    ATX 1.jpeg
    176.4 KB · Views: 19
  • ATX bottom.jpeg
    ATX bottom.jpeg
    182.8 KB · Views: 18
  • ATX Top 1.jpeg
    ATX Top 1.jpeg
    193.2 KB · Views: 15
  • ATX Top 2.jpeg
    ATX Top 2.jpeg
    924.2 KB · Views: 15
  • ATX Top 3.jpeg
    ATX Top 3.jpeg
    182.2 KB · Views: 19
  • Board Reverse (Copy).jpeg
    Board Reverse (Copy).jpeg
    1.9 MB · Views: 19
  • Board view 1.jpeg
    Board view 1.jpeg
    212.8 KB · Views: 20
  • Board view 2.jpeg
    Board view 2.jpeg
    1.3 MB · Views: 15
  • Motherboard.jpg
    Motherboard.jpg
    429 KB · Views: 17
Did you check F3? It is a fuse that probably feeds some of the power to Q15 and Q14.
Remember that the PSU needs a "start" signal (usually the green wire to ground) to in effect turn on.
Try a different power supply if possible...
 
If there is no standby power, it's likely a PSU fault.

With the PSU not connected to the motherboard but powered on, do you get 5V between the purple 5V standby wire and one of the black ones?
 

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