Originally Posted by jaredpace

PLEASE POST IF YOU CAN GET THIS TO WORK ON G92 OR G80 CARDS.
Thanks to JustaGeek95 and Unwinder.

Info:
The steps highlighted in this process are basically equal to what Evga voltage tuner, and Gigabyte gamer HUD alter to allow the end user control of the video card's voltage. Gigabyte actually adds a voltage chip to it's reference boards that the drivers control. This requires a bit of experience & expertise, but a simple boob-friendly GUI should surface quickly.

So far people have this working on HD4800 & GT200 cards, not sure if it works on older generations.

Hopefully more people will contribute to this and create some great software GUI (like evga voltage tuner). We need "slider control" of fan speed, gpu voltage, and gpu/shader/mem clocks for single and multi-card setups. If we could just add this to RT - it already has all the advanced options, schedules, and profiles.

Originally Posted by 003

I would pay money for RT if it had GUI based voltage adjustment. And hell. Warnings aside, it could be set up so that the only way to access the voltage adjustment would be through an obscure ini tweak. That would prevent anybody who didn't know what they are doing from using it

Originally Posted by mattkosem

Actually, as I look back through the post, it looks like the formula was listed incorrectly. I can see from the formula that is used to calculate the desired vid that it should really be:

voltage = (VID * 0.0125) + 0.45

That pointed me to 18 being the correct one, so I ran:
RivaTuner.exe /sd0 /wi1,70,18,4C /sd2 /wi1,70,18,4C

Boom! 1.4v!

--Matt

Originally Posted by justageek95

DISCLAIMER: I TAKE NO RESPONSIBILITY FOR ANY DAMAGE THAT MAY HAPPEN IF YOU DO THIS!

1. Find the I2C bus of your card by running the following CLI commands:
RivaTuner.exe /ri0,70,1A
RivaTuner.exe /ri1,70,1A
RivaTuner.exe /ri2,70,1A
RivaTuner.exe /ri3,70,1A
Three of these four commands will return "invalid" take note of the one that doesn't (for me it was /ri3,70,1A)
This will find the I2C bus (highlighted in red in my example)

2. Get your voltage register values
Using the I2C bus number found above, (0-3, highlighted in red) run the following CLI commands, replacing "#" with the I2C bus number.
RivaTuner.exe /ri#,70,15
RivaTuner.exe /ri#,70,16
RivaTuner.exe /ri#,70,17
RivaTuner.exe /ri#,70,18
Take note of the return value for each.

3. Convert voltage register values to actual voltage
For each of the values returned in step 2 do the following:
A. Convert the value to decimal format (the returned values are in hexidecimal)
B. Calulate actual voltage by the formula: voltage = (VID * 0.0125) + 0.45
C. Compare the 4 resulting actual voltages to the voltage reported in 3D mode in Rivatuner hardware monitoring.
D. The closest value should be your 3D voltage (ex: for me Rivatuner showed 1.13v, I got 1.250v
E. Take note of the register that is associated with that value. (highlighted in red in step 2)

4. Calculating the voltage to use
A. Decide what voltage you want to set.
B. Find the VID for that voltage using the formula VID = (voltage - 0.450) / 0.0125
C. Convert the VID to hexadecimal

5. Setting a new voltage
You can set the voltage by writing the new VID in hexadecimal form to the register.
A. Run the CLI command: (replace # with IC2 bus number, and VID with the VID in hexadecimal form)
RivaTuner.exe /wi#,70,17,VID

The new voltage should now be set!



Example: GTX 260, desired voltage = 1.2v

1. All the commands return "invalid" except RivaTuner.exe /ri3,70,1A which returns "0A"

2. I get the following values:
RivaTuner.exe /ri3,70,15 returns 3B
RivaTuner.exe /ri3,70,16 returns 31
RivaTuner.exe /ri3,70,17 returns 36
RivaTuner.exe /ri3,70,18 returns 2F

3. Calculating the voltages of each:
Hex: Decimal: Voltage:
3B......59......1.1875v
31......49......1.0625v
36......54......1.1250v
2F......47......1.0375v
Rivatuner was reporting 1.13v in 3D mode so the third one is my 3D voltage register.

4. I wanted 1.2v so:
VID = (1.2 . 0.45) / 0.0125 = 60
60 = 3C in hexadecimal

5. I set the new voltage by running:
RivaTuner.exe" /wi3,70,17,3C

Originally Posted by Unwinder

A few tips and tricks:

1) Once you've determined index of I2C bus containing VRM on some display adapter (e.g. I2C bus 3 on GTX 200 series), the same index can be safely used on the same display adapter model by others. Display adapters have a few I2C buses assigned for differed functions (e.g. for connecting DDC and for external devices like VRMs, thermal sensors, fan PWM controllers and for on), VRM's I2C bus is defined by PCB design so it is fixed for the same display adapter families.
2) Don't try to scan more I2C buses than the GPU actually has (there was some posting with attempt to scan buses 0-99 in hope to find VRM on G92). Each GPU architecture supports fixed number of I2C buses, e.g. G80 and newer GPUs have only 4 I2C buses, pre-G80 supports 3 buses, pre GF4 supports just 2 buses and so on.
3) I see that many users started to enable VT1103 plugin now. Please pay attention to the following info from RivaTuner's release notes and always remember about it when using this plugin:

"Please take a note that Volterra voltage regulators are rather sensitive to frequent polling and may return false data under heavy load, so it is not recommended to use VRM monitoring in daily monitoring sessions"

4) There were some questions about finalizing these new VRM settings in NVIDIA VGA BIOS. You cannot use Nibitor for that because the tool knows nothing about VRMs and works with BIOS voltage tables only, it is only allowing you to change associations between performance levels (i.e. 2D/3D modes) and 4 fixed voltages stored into VRM registers 15-18 by default. However, you can easily edit your BIOS with any hex editor to reconfigure initialization scripts writing these 4 fixed voltages to VRM during POST. It is rather simple task, taking my 65nm EVGA GeForce GTX 260 as example the following script command in VGA BIOS is configuring VT1165:

4D 80 E0 06 15 3B 16 31 17 36 18 2F 1D 55 19 01

The command uniquely identifies I2C serial byte write operation, encodes target I2C device address (E0 is 8-bit encoding of VT1165's 7-bit address 70 including read/write flag in the first bit), tells script processor how many bytes have to be written (06) and finally defines register addressed and data to be written to each register (register 15 -> 3B, register 16 -> 31 and so on).
The voltages can be different for different VGA BIOS images, so the easiest way to locate this command in any GTX200 BIOS image is to search for 4D 80 E0 byte chain.

Please read my previous comment about I2C bus indices, altering I2C bus indices is not a correct way. You should try to probe difference i2c device addresses instead. Each I2C device address is defined by developers (e.g. ADT7473 fan controller use fixed address 2E, VT11xx VRMs use fixed register 70 by default, but it can be strapped to 7x AFAIR, etc).
You must have Primarion PX3544 datasheet to know where it normally resides. I've peeked inside reference 9800 GTX BIOS to see if it is initializing any I2C devices and it does seem to write something to I2C device 6A (writes single byte 86 to register 80 of this device). It can be Primarion PX3544, but I've no strict info about it because I don't have any info on this VRM I2C interface.

Originally Posted by drifter

TX man!
works on my gtx 280

http://www.easycalculation.com/decimal-converter.php
http://www.maxi-pedia.com/hex+to+decimal+converter

hex to dec and dec to hex converters
edit: does anyone know how to get it running at rivatuner/pc startup

Originally Posted by auchkoenig

It working on my GTX280 too but I have a question though. The given cli only change the VID for gpu0, how do I change the VID for gpu1 since im using SLI.

I tried checking the diagnostic report. The only difference between the two GPU is one is on

$0000000003 Location : bus 2, device 0, function 0

and the other one is on

$0000000003 Location : bus 3, device 0, function 0

My guess is that i need to change the deviceid, am I correct?

Originally Posted by Unwinder

You should apply changes to both GPU VRMs. CLI works with GPU selected in the main tab of RivaTuner. There is /sd<device_index> or /selectdevice<device_index> command allowing to change device selection via CLI. <device_index> is 0-based logical display device index, i.e. if there are 4 virtual display devices (2 heads representing independent displays for the primary GPU and 2 more heads for the secondary) then your should select the first (0) then the third (2) logical devices when applying the changes. In this example, command line for probing VRMs of both GPUs can look like:

RivaTuner.exe /sd0 /ri3,70,1a /sd2 /ri3,70,1a

Originally Posted by Unwinder

RivaTuner's task scheduler module was designed special for such tasks. Go to <Scheduler> tab, click <Add new task> button and type in task name, e.g. "Voltage mod", select <Launch application on specified schedule> task type in %RT% macro as path (RivaTuner will expand it into fully qualified path to itself when executing) and desired I2C writec commands in the command line field then selct desired schedule type, e.g. <Run task at RivaTuner startup>.

Originally Posted by Asus Mobile

Do it and post back let us know how it goes.

Originally Posted by trueg50

Like I said in the other thread, I do not at all recommend this mod.

It is stable in Furmark, but not in any game at all. Even maintaining the same clock speeds, and only upping the volts to 1.4.

Also, even if you restart (thus undo the mod) it will still mess up your card until you fully uninstall Rivatuner. It was a royal pain with a volt mod, till I figured out that Rivatuner's voltage adjustment was still messing with the voltage.

Originally Posted by 10acjed

If you follow over to the OP at xs you will see pages upon pages of people not getting any gains from this, mostly they are running ATI cards, I havent seen many posts from what I read that anyone really got anything out of this either..

I know I have gotten a little benefat from a bios mod to 1.1 on my old 8800GT. But I have yet to even tinker with this new card...

muffing up my old 8800 was one thing, could replace that for 80$. I would cry if I did it to this 285

I am continuing to monitor progress from people. I will updat with good news if I find any.

Originally Posted by killerhz

I did this mod with both my 260's was furmark and ATI tool stable. Tried to run Vantage or Games and system froze up. I messed around with it for about 2.5 hours and nothing helped.