gigabyte gtx 1070 caps, inductors and mosfets short

[Hw31]

hey there,

specific questions:

so i have gtx 1070 which isnt detected where the caps, inductors and mosfets are short. Circled red. can i just inject voltage in the red circled pads? if yes, how much volt and amps are safe?

general question:

is there a tutorial on how to proceed with an defective graphics card? like check this first, then this, then this.if this component is falty it means that, or also something else could be bad etc.?
i know there are differnt rails and so on but these are on different places depneding on the board layout. how to find out where they are? i poked around a bit and it seems there is only 16V? present.

best regards


https://imgur.com/a/sZZkY3s

[dicky96]

Re: gigabyte gtx 1070 caps, inductors and mosfets short

Hi HW31
Are you sure you have a short? The GPU can read very low resistance to ground - typically less that 1 ohm (like 0.6 ohm is quite normal)

What resistance do you see from the big square inductor coils (marked magic 15) to ground?

What resistance do you see from the same big square inductor coils to 12V (check on the yellow wires on the 8 way connector and also the 12V pins on the PCIe connector)

https://hardzone.es/tutoriales/rendi...i-express-3-0/

The point where you are asking if you can inject voltage - this would be the Vcore voltage so typically about 0.9V or so. The injected current would be high for a working card, typically 100A or more

You could inject voltage with something like this
https://www.tomshardware.com/news/ep...wer,35497.html

I have one on my shopping list

You could also cobble something together using the VRM section from a scrap GPU - this is something on my 'to-do' list

Rich

[Hw31]

Re: gigabyte gtx 1070 caps, inductors and mosfets short

What resistance do you see from the big square inductor coils (marked magic 15) to ground?

0.04 ohm

What resistance do you see from the same big square inductor coils to 12V (check on the yellow wires on the 8 way connector and also the 12V pins on the PCIe connector)

pcie = over 2Million ohm and increasing? maybe a bad resistor?
8 way connector: pin1: 7.63 kOHM, pin2&3: 3.4 kOHM


thx!

[dicky96]

Re: gigabyte gtx 1070 caps, inductors and mosfets short

Did you measure the 0.04 ohm on resistance mode or diode mode?

[Hw31]

Re: gigabyte gtx 1070 caps, inductors and mosfets short

Resistance mode

[dicky96]

Re: gigabyte gtx 1070 caps, inductors and mosfets short

That sounds like a short. Could be GPU or if you are lucky a capacitor somewhere

In my previous experience on a very similar fault (different Geforce card) it was an MLCC capacitor but I couldnt' determine that it was a capacitor without removing the GPU first

[DynaxSC]

Re: gigabyte gtx 1070 caps, inductors and mosfets short

Hi,

Regarding a GTX1070, the GPU (GP104-200-A1) should have some 0,13 ohm resistance, provided you measure with a meter, which is suitable to measure such low resistances. All the usual universal meters are not suitable. You need to have a special meter, which has 4 wires, so it is not taking into account the resistance of the measurung wires. Also usual meters are not calibrated so exactly. If you have good resolution meter, eg. 4 digit you can try to measure the short resistance, and the meter cable resistance, and calculate the real short resistance as a difference. That way you may get a result which is somewhere around reality.

You can buy such 4-wire meters on Aliexpress, they are not so expensive, but have chines menue only, but they are really good for that task.

Regarding the monolythic caps, you can try to inspect them with an good magnifier glass. That which have shorts, you often can see some irregularity, eg a very thin scratch on them. That way you can identify the shorted ones quite often. thgen you just take off such a one, and look if the short persists. The shorts are ofetn on the 12V supply voltage, much more ofetn then shorted GPU's. So most probably the caps or the mosfets, GPU's get rather seldom broken, mostly due to bad cooling. I have even seen gpu's with broken silikon, but still functioning, however the temperatures were very fast very hot.

[dicky96]

Re: gigabyte gtx 1070 caps, inductors and mosfets short

@DynaxSC
He is reading less than 0.13R so the resistance of his meter leads would not make a difference in this case - they could only increase the reading not decrease it. Of course his meter could be reading incorrectly if it is not well calibrated.

Can you post a link to one of the 4 wire meters you mention on Aliexpress - I'm interested.

Thanks
Thanks

[DynaxSC]

Re: gigabyte gtx 1070 caps, inductors and mosfets short

Hi,

It's called YR2050 miliohm meter (sold by Good Idea Store):

https://www.aliexpress.com/item/4000...85565769%22%7D

The device works in chinese, but it's easy to discover how to use, it can measure really low resistances and is quite precise, looks maybe not very nice, but it makes it's job. You can also translate the user manual with OCR and google translate to your language. A very big difference compared to normal univerasl meter.

[DynaxSC]

Re: gigabyte gtx 1070 caps, inductors and mosfets short

And regarding the 0.13ohm, it's measured directly on the GPU supply, which is to be accessed on the coil leads which are opposite to the mosftes. Usually the short is on the primary 12V side, and still then the 0,13 ohm can be measured on the coils opposite to the mosfets. If you measure on the mosfets, then you get near 0,0 result, but it depends if mosfets are short or only buffering caps on 12V line, and mosftes are OK. If mosfets are shorted, then also the 0,13 ohm reading will be much lower, also if the GPU is short.

[DynaxSC]

Re: gigabyte gtx 1070 caps, inductors and mosfets short

Just read in the comments on Aliexpress, the seller can send an english manual.

[dicky96]

Re: gigabyte gtx 1070 caps, inductors and mosfets short

Hi,

It's called YR2050 miliohm meter (sold by Good Idea Store):

https://www.aliexpress.com/item/4000...85565769%22%7D

Thanks for the link - it looks interesting

[elgesetia]

Re: gigabyte gtx 1070 caps, inductors and mosfets short

I have Gigabyte GTX 1070Ti, and both R5372 and R5373 are burning, to everyone here, can you help me find the voltage of this resistor? Thanks before

[dicky96]

Re: gigabyte gtx 1070 caps, inductors and mosfets short

Resistors don't have a voltage rating. They have a wattage rating (which effectively is a maximum current rating)

If these resistors are burning then almost certainly there is a short circuit to ground on one end of them