Mine card P106 power supply problem repair

The problem with the power supply of mine card P106 is that the 5V feedback resistor is knocked off, resulting in abnormal feedback. Then the 5V chip generates 12V, which destroys the core power supply composite tube and pex power supply chip.

Machine model: mine card P106

Fault phenomenon:power supply problem

Maintenance process: the resistance of the external power supply measured by the hand is normal. The card is not recognized when the power is turned on. The current of the adjustable power supply is only 0.19.

Mine card P106 power supply problem repair Figure 1.

The current is obviously abnormal, indicating that there must be power supply for this card. After disassembling the video card, measure the ground resistance of each power supply, and find that the ground resistance of the five volt is low.

Mine card P106 power supply problem repair Figure 2.

In case of such short circuit, cook chicken directly. A two V voltage is clamped, and then the problem arises.

Mine card P106 power supply problem repair Figure 3.

It was found that a core powered composite tube was short circuited.

Mine card P106 power supply problem repair Figure 4.

Remove the composite pipe, and the 5V resistance will return to normal.

Mine card P106 power supply problem repair Figure 5.

At this time, I didn’t repair this composite tube. I’m going to power it on first to check if 5V is abnormal. If it is normal, I will repair this composite tube. As a result, there was a problem at this time. Once the power was turned on, it was found that there was a short circuit again.

Then using the thermal imaging burner, it was found that another composite tube was also burnt. At this time, it was suspected that there was a problem with the 5V. However, since the current state was short circuit, the short circuit could only be eliminated first, and the other two composite tubes could also be removed together.

After the other two composite pipes were disassembled, the measured 5V to ground value was normal, so the power was turned on again, and then the short circuit occurred again. I had no choice but to cook chicken again. At this time, I found that the chip powered by PEX was broken.

After this wave of operation, there was no way to deal with the loss, so we had to continue to repair. After removing the PEX power supply chip, the 5V is measured again and found to be normal. At this time, observe the motherboard except for the core power supply chip,

The other chips are basically removed, so at this time, we can only power them again.

Finally, it was found that the five volt voltage had changed to 12 volts, which led to the burning of so many front composite tubes and chips. Later, after some searching, it was found that the 5V feedback resistor was knocked off, which caused the feedback problem, but the chip was not protected. Finally, after the two feedback resistors are added, the 5V voltage is normal.

Finally, three core powered composite tubes and one PEX powered chip are added. The maintenance of this card is over here.

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