COLORFUL GTX 1060 3GB- fire mosfet .please help me

[conghuyms]

I have a COLORFUL GeForce GTX 1060 3GB that is not working. After replacing the NCP81174 ic, the card works again. but 2 mosfets Q625 and Q619 fire . Replaced 2 mosfets Q625 & Q619, still burned. the position I marked in the attached image.
please help me. thank you so much

[Prott]

Re: COLORFUL GTX 1060 3GB- fire mosfet .please help me

Check the resistors and capacitors attached to that phase. Some of them might have changed their values. You can also check the drivers of that phase - first visually but also try to compare resistances to other phases.

[DynaxSC]

Re: COLORFUL GTX 1060 3GB- fire mosfet .please help me

I would guess the driver of that phase is broken, check the resistance on the power supply pin of that driver, and check it against other drivers. To do it correctly you have to remove the serial resistors (usually 2.2 ohms) in series to the power supply pin to that driver. If no serial resistor present, you have to remove 2 drivers from the board, and check them off-board (tricky). Sometimes is the driver has a short on power supply pin, the serial 2.2 ohms resistors may become seriuosly decalibrated (eg 50 ohms) or even burned with no conductivity. Second check you can do is after replacing the bad mosfets, check the resistance on the gates of the three mosfets, they should be same as on other phases (usually 10 kohms to even Mohms, depends on card) - but do not power the card. Check also the resistance on the GPU Vcore, it should be over 0,15 -0.2 ohms - you would need to have a special low resistance meter to do this exactly, any usual meters are not suitable to measure such low resistances. If during the fire of the mosfets the GPU got a too high voltage (over ca 1.2-1.5V) then the GPU might be dead. This can happen, if the high side mosfet is the first which becomes shorted, and puts the full 12V voltage on the GPU. Anyway if you fix the VRM, you will know if the GPU is good or dead. A dead GPU will have a total short, so VRM should should shut off or limit the current, and no VCore will be present.

[conghuyms]

Re: COLORFUL GTX 1060 3GB- fire mosfet .please help me

thank you my friend, it's working

[conghuyms]

Re: COLORFUL GTX 1060 3GB- fire mosfet .please help me

I would guess the driver of that phase is broken, check the resistance on the power supply pin of that driver, and check it against other drivers. To do it correctly you have to remove the serial resistors (usually 2.2 ohms) in series to the power supply pin to that driver. If no serial resistor present, you have to remove 2 drivers from the board, and check them off-board (tricky). Sometimes is the driver has a short on power supply pin, the serial 2.2 ohms resistors may become seriuosly decalibrated (eg 50 ohms) or even burned with no conductivity. Second check you can do is after replacing the bad mosfets, check the resistance on the gates of the three mosfets, they should be same as on other phases (usually 10 kohms to even Mohms, depends on card) - but do not power the card. Check also the resistance on the GPU Vcore, it should be over 0,15 -0.2 ohms - you would need to have a special low resistance meter to do this exactly, any usual meters are not suitable to measure such low resistances. If during the fire of the mosfets the GPU got a too high voltage (over ca 1.2-1.5V) then the GPU might be dead. This can happen, if the high side mosfet is the first which becomes shorted, and puts the full 12V voltage on the GPU. Anyway if you fix the VRM, you will know if the GPU is good or dead. A dead GPU will have a total short, so VRM should should shut off or limit the current, and no VCore will be present.

Thank you very much ! My friend