GTX 1070 missing 1V please help

[tonycstech]

HI i have my 1070 missing 1v and everything else after that.
5V and 12V present.
The U7 chip on the board does get 5v and 3.3v but nothing on the EN pins

U7 chip is uP1728QDDA
I attached a photo of the card. Coil next to the U7 chip should read 1v as shown in red and 83 ohms shown in yellow.

where do i look for a problem ?

[manuforti1314]

Re: GTX 1070 missing 1V please help

I think the enable for U7 (pin 10) comes from the 1.8v rail, there is a 10k resistor in between 1.8v and the enable. Might be that?

Resistor might be marked R183.

[tonycstech]

Re: GTX 1070 missing 1V please help

10k resistor reading.
Not that i guess.

[manuforti1314]

Re: GTX 1070 missing 1V please help

10k resistor reading.
Not that i guess.

Do you have continuity from 1.8v to the enable pin?

[tonycstech]

Re: GTX 1070 missing 1V please help

9k from U7 (10th pin EN) to L20 (1.8v)
1.8v is missing also.

[tonycstech]

Re: GTX 1070 missing 1V please help

Also, U505 chip (uP9511) has nothing on EN pin.
Not sure how many volts suppose to get there but its 0v

[manuforti1314]

Re: GTX 1070 missing 1V please help

Have you watched this video?

https://youtu.be/SmVdl8kew_4

I found this really useful, chapter 6 covers the power sequence of cards (10 series cards are the left column at https://youtu.be/SmVdl8kew_4?t=5629), if you have 5v i think next is 1.8v, if you don't have 1.8v then you need to start troubleshooting that.

I use the boardviews and schematics as well, helps me find and trace connections. Use PG413 boardview for a 1070, it's actually nearly the same although a 1080.

[gt403cyl]

Re: GTX 1070 missing 1V please help

Most Pascal cards use the same PEX rail circuit. (the 1v rail).

https://repair.wiki/images/2/29/Pex_...tic_pascal.jpg