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Old 05-23-2013, 01:35 AM
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TiN TiN is offline
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Join Date: Jan 2010
Location: Taipei
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Talking Uncorking BIG KELPER - practical guide for beginners. Show must go on!

780 is in wild now, so we made something up here to have more fun with them.
This guide is 100% applicable to bigger brother, TITAN as well, because both cards share same PCB from power delivery point of view, so for those who need - enjoy.

I'll skip regular vmods and other baby stuff in this guide, it was already posted on web, and for that new GTX780 is exactly same as Titan,
so hold on, lets jump straight to serious stuff here.

New EVGA E-POWER "The Untouchables" CLASSIFIED

One of most successful cards for using with zombie power was GTX 680. Relatively low power consumption and high performance was playing good together with
added complexity of using external VRM. Desprite of voltage droop and not optimal current path that combo was still able to impress overclocking community
by delivering over 1900MHz GPU clocks stable enough to break records in heavy 3D'11 benchmark. But now, with GK110 big brother we can say bye-bye to low
power consumption. 7 billion of tiny mosfets dying from hunger, and we need to satisfy their needs if we want to get decent scores from card.
But in real world overclocking is not most important thing, so reference TITAN and GTX 780 are just good enough for their stock clocks and voltages, but
nothing above. Few brave guys tried to prove that wrong, but were quickly taught 1000$ USD lesson of fried electronics.

So I had a clear task in front of me - we need some real stuff, something that can hold TITAN-class power drednought like a toy.
And using experience we gained on GTX 580/680 CLASSIFIED designs, and my own observations on zombified GTX 580, GTX 590, GTX 680, GTX 690 with our good but now obsoleted
10-phase Volterra-based Untouchable I came up with digital-based IR VRM with 14-phases, just as our 680 CLASSIFIED VRM minus memory power and VGA-related stuff.
As I show later, I wanted to include few nice and useful features to make usage easier and better power delivery.

Since today, wait is over, now everyone who is capable to hold soldering iron and have balls to loose warranty for their VGA forever - now
can have key component of CLASSIFIED-branded EVGA graphics card on their own VGA, any model, any vendor, any color, even ATI

Lets take a look, and go thru process of zombifying brand-new fresh NVIDIA GeForce GTX 780 I have here on my desk.

That's overview of everything important we will need today:

* Any vendor VGA card
* EVGA EVBOT for voltage adjustments
* 80-150W soldering iron (need lot of beef to solder on power planes, due to good thermal dissipation. Your 25W SMD iron will NOT WORK)
* Soldering FLUX
* Heavy-duty cutters for metal
* Copper pads/plates (1-2mm thickness is best, still easy to bend, and nice low resistance connection)
* Kingpincooling TEK9 FAT (don't forget who's forum is here, yes
* DMM (I use Fluke 87V and Keithley 2001, but any DMM can fit this needs)
* Low-ESR capacitors (2.5 or 4V rated, 680-820uF , etc)
* Some VRs for regular vmods for memory, PLL, etc (not shown on photo)

Pretty standard list, only new thing - copper plates. I found them better than crazy wires because they are not flexible (can fix position and then solder it firmly easier),
have lower resistance, and easy to reuse. Also no burning wire insulation and nasty smoke, which is healthier for overclocker :P
I buy these at local PC cooling parts shop, but pretty sure those are not hard to get all over the world in some metalwork shops, etc.


Get rid of fancy heatsink, chop off goofy VRM from our GK110 by removing 6 power inductors.

There coils are easy to remove with 150W iron, just heat one side up and lift it.
Then desolder second side and remove a choke.


Do your memory voltage mods, or anything you want on VRM PCB area.
Don't repeat stupid TiN-ba mistake, who connected EPOWER and realize after all work alredy done that there was no memory mod done, and
that area under EPOWER have no access now.


Cut a magic trace and say BYE-BYE to your GTX 780/TITAN warranty. Who need that stuff anyway, right?

Don't try to be smarter, there is no other resistor/component/way, other than cutting trace. If you don't agree - ok, write your own guide then


When using external VRM the bottleneck is always interconnect between target board-victim and power source board.
That is why no connectors can be used to make "customizable" EPOWERed VGA, or "configurable" VRM.
When you think about currents (hundreds of AMPs) and voltages (less than 2V most of time) and required regulation tolerances (<1% most time),
there is no way that even big power connectors will be good enough to meet those specs.

I mean, yes, some vendors do have product which allow external VRM to be user-connected by some interface connector, but none of those products
received any performance records or gains from such marketed "improvements". Same goes to extra addon boards with capacitors .

So the only answer and option is DIRECT connection with solder, PCB to PCB, with shortest path and widest plane possible.
As a result new EPOWER CLASSIFIED allow you to connect power output to VGA not only by one outer copper layer, but by 4 layers, including 3 interals layers.

To use this option you will need to cut edge of EPOWER card (around 5mm from edge, by start of vias and VCC EDGE marks in PCB).
After doing so - you will see three extra power copper layers exposed on edge. Then do SHHRRR-SHHHRRR on edge to make it smooth and flat and
use solder to interconnect everything together. In terms of marketing there is 400% improvement, but we are serious guys here, so let's just say
it's better


Now let's align EPOWER and VGA together, get coffee/tea/vodka and think a little, how we want to connect both boards together
and minimize current path. You can locate EPOWER from back side, top side, whatever side you think good for your use, it's really up to you.
But in this guide and this particular card my target was next:

* Shortest and widest connection
* 4-way SLI-capable spacing
* Easy access to EPOWER for debug

So this gives only one position - in front of card, with minimum angle to PCB.
It's bad position from ground power plane delivery POV, so I'll need to find alternative way to connect grounds, but it still should be good enough.
If I would need ultimate single GPU style card - I would connect EPOWER under 90 angle to VGA with direct connect of both VCC and GND planes.
New EPOWER CLASSIFIED have VCC OUT copper plane area exposed on top layer (one which have components/heatink on it) and GND plane exposed on bottom layer.




No comments required.
Be careful not to shhhrrr non-power traces/vias :P


I wanted to lift power plane above PCB surface, so i can directly solder EPOWER edge to it.
To do so I made 4-6mm thick copper clads and solder them with LOTS of solder on GPU power plane on VGA.

Don't confuse power with ground. DMM checks on every operation here are essential, to make sure that VCC is still VCC, and
GND is not shorted to it. Good idea to solder DMM probes to VCC and GND so you can monitor resistance non stop.
There is small caveat here, when PCB is hot from soldering - resistance will drift away. Fluke 87V can show negative resitance
with this , like -1.5 ohms for example Don't get fooled, it's delta you are looking for, not some specific value.


Now need to bend shaped copper plates to have nice and robust connection between PCBs.
It's more like half-hour of metal bending, aligning, fitting, bending, fitting, bending, bending, getting angry, bending, bending, saying bad words, bending, fitting...
and only then soldering perfectly matched bent copper plates together, making EPOWER and VGA one solid common thing - called Untouchable.

Here's VCC soldered on front:

Now GND on back

Support GND "leg"

One way to connect GND on front (card on right side)

Another way to connect GND by copper plates connecting capacitor grounds on top with copper GND "wall" between VGA caps and memory IC's.


Now look on abomination monster which you have just created.
Like it? Want to break record with it?
Not so quick, fella! Check your resistances before you put it into system and blow everything apart.

Healthy GK110 GPU usually have ~2-4 ohms. If you have less than 1 ohm - time to find short and go thru all pain of redoing everything again from step 1, but now
worse - because you forgot to follow TiN's suggestion on step seven and need to remove all copper soldering from zombie. It's harder than putting on,
believe me, i went thru this

Healthy mems are around 20-30 ohms for Titan, and 40-70 ohms for 780 (because twice less memory IC's)

Healthy PLL rail resistance is around 100-200 ohms.


Now, after all hardware is good, you can relax a bit, get grease, insulation stuff, best pot in the world, TEK9 FAT 6.66, and start putting
everything together for benching.

Apply vaseline

Melt it.

With pot

And then - it's ALIVE

Don't pay attention to oscilloscope in background, it just there to make "scientific look", nothing else, believe me
Enjoy benching.

Stay tuned, we will show you dirt when Vince show some of his magic to us

Last edited by TiN; 08-03-2017 at 02:30 AM. Reason: added guide
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