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Discussion Starter #1
Yea, I watched all the videos, read all the posts. It seems no one is in agreence of how to actually do this. So what's the deal?

So far I am seeing you shunt 5 resistors, the 4 by the PCI-E ports and 1 down on the bottom for the PCI-E slot. You put 5 milliohm resistors onto of the existing for a 100% power boost. Is this accurate?
 

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There is no Spoon ..... there is no shunt mod.
I am 35 years in electronics repairs, I did watch on YouTube one experiment of how by manipulating the shunt value, the power limiter circuitry changing it behaviour.
The so called benefit was 2FPS.
All Kids screamed that this is a modification worth having.
I think, and believe it, that this is a plain stupidity.
But the man which did the experiment, he worth the credit as tester which he tried something new and his content it is not boring.
 

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Discussion Starter #3
There is no Spoon ..... there is no shunt mod.
I am 35 years in electronics repairs, I did watch on YouTube one experiment of how by manipulating the shunt value, the power limiter circuitry changing it behaviour.
The so called benefit was 2FPS.
All Kids screamed that this is a modification worth having.
I think, and believe it, that this is a plain stupidity.
But the man which did the experiment, he worth the credit as tester which he tried something new and his content it is not boring.
How is it not worth the effort when everyone on this entire forum, and everyone everywhere, is complaining how clearly power limited these cards are? Like crank the slide to +20 MHz and instantly it's power limited.
 

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Facepalm
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There is no Spoon ..... there is no shunt mod.
I am 35 years in electronics repairs, I did watch on YouTube one experiment of how by manipulating the shunt value, the power limiter circuitry changing it behaviour.
The so called benefit was 2FPS.
All Kids screamed that this is a modification worth having.
I think, and believe it, that this is a plain stupidity.
But the man which did the experiment, he worth the credit as tester which he tried something new and his content it is not boring.
10% improvement from me going from 400W to 550W.
So I don't know what you're smoking.
 

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Massive improvement for me going from 350W to 520W in benchmarks on my 3090 XC3.
In games depending on the game thats 5-12fps more which really matters when your after 4K max settings.

Ampere cards a really power gimped. Nvidia knew this when they decided to go with samsung 8nm and the cards should of really release with base power of 400W for 3080 and 480W for 3090 since you have perfect performance scaling up to that point.

But back to the question.
I guess the most proper way would be desoldering all the shunts with hot air and replacing them all. That way you know you have perfect balance between all of them and the bios will work as intended other then the card drawing more power because its reading is faked.
Then next best way would be soldering a extra stack ontop. Which is less perfect since you have the extra restance from each solder joint.
Followed by the conductive paint methods (which is even less perfect since different thicknesses of paint and pressure will effect resistance even further)

On mine I went with conductive paint method so it could be undone if the card failed or a better bios came out (Which it did).
Cleaning up the conductive paint was time consuming but you couldnt even tell it had been done after the clean up and iv been running the 1kw bios but it looks like ill be reshunting again when the new bios come out with resizable bar support.
 
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Massive improvement for me going from 350W to 520W in benchmarks on my 3090 XC3.
In games depending on the game thats 5-12fps more which really matters when your after 4K max settings.

Ampere cards a really power gimped. Nvidia knew this when they decided to go with samsung 8nm and the cards should of really release with base power of 400W for 3080 and 480W for 3090 since you have perfect performance scaling up to that point.

But back to the question.
I guess the most proper way would be desoldering all the shunts with hot air and replacing them all. That way you know you have perfect balance between all of them and the bios will work as intended other then the card drawing more power because its reading is faked.
Then next best way would be soldering a extra stack ontop. Which is less perfect since you have the extra restance from each solder joint.
Followed by the conductive paint methods (which is even less perfect since different thicknesses of paint and pressure will effect resistance even further)

On mine I went with conductive paint method so it could be undone if the card failed or a better bios came out (Which it did).
Cleaning up the conductive paint was time consuming but you couldnt even tell it had been done after the clean up and iv been running the 1kw bios but it looks like ill be reshunting again when the new bios come out with resizable bar support.
Power gimeped? 520W is insane. 7nm would have done nothing. Its all down the crazy large CUDA cores and power-hungry memory. 3080 uses 110w just memory alone. Nvidia would have save a lot of power and gotten a lot of perf if they had gone HBM2.
 
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People claim overclocking, or modifying components, isn't worth it but honestly you are spending very little to nothing for a gain in performance. So for my it is almost always worth it. This all assumes you know what you are doing and don't break anything.
 

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Did you shunt mod it?
Yes I even posted a picture of a 550W Port Royale stress torture temperature loop in the 3090 thread.
 

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Discussion Starter #10
Yes I even posted a picture of a 550W Port Royale stress torture temperature loop in the 3090 thread.
What did you shunt? The four shunts by the power ports and the 1 shunt down by the PCI-E slot for a total of 5? Did you use 5 or 8 milliohm shunts?
 

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What did you shunt? The four shunts by the power ports and the 1 shunt down by the PCI-E slot for a total of 5? Did you use 5 or 8 milliohm shunts?
Huh? There are 6 shunts, not 5. Who told you there were 5?
8 pin 1, 8 pin 2, MVDDC, GPU Chip, Input power plane Source, PCIE Slot.
I used MG 842AR conductive silver paint.
 

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Discussion Starter #12
Huh? There are 6 shunts, not 5. Who told you there were 5?
8 pin 1, 8 pin 2, MVDDC, GPU Chip, Input power plane Source, PCIE Slot.
I used MG 842AR conductive silver paint.
Sorry, 6. Forgot the one on the back. I am new. So these six, right? For some reason I was thinking the top four were just for the +12v connectors and the bottom two were just for the PCI-E slot. E.g. two shunts per port.

Are you conserned about blowing the fuse on the PCI-E slot? It looks like it has a lower value fuse (15A maybe?) than the 20A fuses on the +12v slots.

2474086
 

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Discussion Starter #13
I also wondered if the hot glue trick works. That is, stick the new shunt on top of the old one and glue it into place with hot glue.

 

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No fuses on the pictures you posted.
Dont hot glue it, thats idiotic.
 
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Sorry, 6. Forgot the one on the back. I am new. So these six, right? For some reason I was thinking the top four were just for the +12v connectors and the bottom two were just for the PCI-E slot. E.g. two shunts per port.

Are you conserned about blowing the fuse on the PCI-E slot? It looks like it has a lower value fuse (15A maybe?) than the 20A fuses on the +12v slots.
3090 FE does not have fuses.
And please don't watch any of framechasers videos. That guy is a complete moron and a half. The only thing he was ever right about was the PCIE slot power limiting issue on the FTW3.
 
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Discussion Starter #16
No fuses on the pictures you posted.
Dont hot glue it, thats idiotic.
No, the pictured card does not have fuses but my 3080 XC3 does. It has 20A fuses on the +12 ports and a fuse of an unknown value on the PCIE slot.

So you think the silver conductive pen is the best bet for a mod that can be cleaned up for warranty purposes? I am wondering how thick you apply the compound, whether there is a risk of it dripping down on the PCB and what the new power cap would be since the resistance is unknown.

Another idea was to use conductive paint to try to 'glue' the resistors on top. That way you at least know the exact power you're working with. Something like this:


I guess alternatively you could also use that paint and just run it over the shunt as well.
 

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Use MG 842AR.
1 layer = 15 mohm.
2 layers = about 13 mohm.
5 layers = about 10 mohm.

It drys hard.
Other wise use it between the contact patch of the shunt you want to stack ontop.

Both I and Falkentne have written guides on here how to do it.
And I also released this tool for working out what your new power limit would be.
 
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No, the pictured card does not have fuses but my 3080 XC3 does. It has 20A fuses on the +12 ports and a fuse of an unknown value on the PCIE slot.

So you think the silver conductive pen is the best bet for a mod that can be cleaned up for warranty purposes? I am wondering how thick you apply the compound, whether there is a risk of it dripping down on the PCB and what the new power cap would be since the resistance is unknown.

Another idea was to use conductive paint to try to 'glue' the resistors on top. That way you at least know the exact power you're working with. Something like this:


I guess alternatively you could also use that paint and just run it over the shunt as well.
That "Bare" paint you linked is graphite based and can NOT be used as a shunt resistor--the resistance will be too high. It can be used as a conductive adhesive to "stack" shunts without soldering (due to resistance affecting the stacked shunt effectiveness, I would go no higher than 5 mOhm shunts for stacking with that), on a board that has the original shunts "flush" and "flat" (middle black part being slightly below or the same elevation as the silver edges, but NOT ABOVE the silver edges!), but I have not tested that. Definitely not for shunts that have depressed edges due to issues getting proper contact--use MG842AR instead. In general, use the MG842AR for both its own shunt (painting the entire shunt fully, completely) or for shunt stacking.

On boards that have shunt edges depressed below the middle housing, you may have contact issues getting the paint applied properly. Make sure you use protective super 33+ tape!!

On some boards you will need to scrape the edges of the shunts (the silver part) with a small flat blade to remove the conformal coating--this is required for proper contact with the paint.

No risk of dripping it on the PCB if you use this.


Perfect for paint protection. Peels right off without any risk to components.

If you are soldering shunts, use high temp Kapton tape to protect your PCB instead.
 

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There is no Spoon ..... there is no shunt mod.
I am 35 years in electronics repairs, I did watch on YouTube one experiment of how by manipulating the shunt value, the power limiter circuitry changing it behaviour.
The so called benefit was 2FPS.
All Kids screamed that this is a modification worth having.
I think, and believe it, that this is a plain stupidity.
But the man which did the experiment, he worth the credit as tester which he tried something new and his content it is not boring.
Have you used any hardware that isn't almost 15 years old? Or do you just use core 2 stuff and give people bad advise on something you have never even used. Every high end gpu 1080 and on has been power limited and benefits from shunt mod.
 

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Discussion Starter #20
That "Bare" paint you linked is graphite based and can NOT be used as a shunt resistor--the resistance will be too high. It can be used as a conductive adhesive to "stack" shunts without soldering (due to resistance affecting the stacked shunt effectiveness, I would go no higher than 5 mOhm shunts for stacking with that), on a board that has the original shunts "flush" and "flat" (middle black part being slightly below or the same elevation as the silver edges, but NOT ABOVE the silver edges!), but I have not tested that. Definitely not for shunts that have depressed edges due to issues getting proper contact--use MG842AR instead. In general, use the MG842AR for both its own shunt (painting the entire shunt fully, completely) or for shunt stacking.

On boards that have shunt edges depressed below the middle housing, you may have contact issues getting the paint applied properly. Make sure you use protective super 33+ tape!!

On some boards you will need to scrape the edges of the shunts (the silver part) with a small flat blade to remove the conformal coating--this is required for proper contact with the paint.

No risk of dripping it on the PCB if you use this.


Perfect for paint protection. Peels right off without any risk to components.

If you are soldering shunts, use high temp Kapton tape to protect your PCB instead.
Ok, I'll just go with the silver conductive paint and paint over the top of the shunt. I have an Evga XC3 which has raised edges on the OEM shunts. Can the silver paint drip down or flake off, or is it pretty robust stuff?

I still have the issue with the 10A fuse on the PCI-E slot. I would obvousaly just paint over it with the silver stuff, although I dont know how much that will add to the amperage rating. My card is on water, but my block doesent contact the power chokes for whatever reason (EWKB dident think it was important I guess). I am wondering if the power chokes will overheat as this is only a 17 phase card.
 
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