My water cooled GTX 280 story.

[Talonman]

I think I have verified my 280's max settings for all three now, core, shaders, and memory...

I already knew my shader limit for sure, and my core, but wanted to spend more time finding my memory's max setting. As it turnes out, I already had it.

I had been running my memory at 1296 error free.

I tried setting the memory to 1350, but that makes ATI tool ring the artifact bell non stop. I did give 3DMark06 a run at that speed, but it caused my system to re-boot. 1350 is out for sure on my card.

I thought 1332 was going to work for me, but in the name of stability, I think I am going to have to give it up... 1332 did pass both 3DMark06 and 3DMark Vantage just fine. ATI tool however, when left to run an extended amount of time, would detect an artifact and reset the timer. It would run 5 to 10 minutes before hitting 1 error, and resetting the timer.

I then set my memory to 1323, and ATI Tool ran error free for over 30 minutes. I really thought 1323 would be my new victory number. I shut down ATI Tool, and fired the Cryostasis Tech Demo up, it ran 1/2 way through, then re-booted my system. Man-O!!

I then set my memory back to 1296, and re-ran the Cryostasis Tech Demo numerous times, and not one single re-boot. I have also tested FurMark, 3DMark06, 3Dmark Vantage, UT3, Dead Space, Starfleet Command III, and GRID. All programs passed with flying colors.

The EVGA Voltage Tuner does not allow for a higher memory voltage, so I am not expecting any gains here. I would love to be surprised on that. Is there any reason to think memory might run faster too, by adding more volts to the core?

I feel pretty darn firm, that my 280's max settings before the voltage tool is: Core=756, Shaders=1512, and Memory=1296.

If think I will be able to tell with 100% certainty, if this tool helps my 280 out any.

I can say this... Using the info from this page:
http://www.ocxtreme.org/forumenus/showthread.php?t=4427

I figured out that my 280 is in the fourth bus, 03 I2C.

My 4 registers are set like this, using BIOS v62.00.0E.00.00 in my 280:
Register 15 - 1.1875v (Performance 3D Mode)
Register 16 - 1.0625v (Low Power 3D Mode.)
Register 17 - 1.125v (Unused voltage entry.)
Register 18 - 1.0375v (2D Mode.)

Using RivaTuner's monitoring tools:
When my core is at 300, my voltage reads 1.04v, looks like register 18.
When my core is at 399, my voltage reads 1.06v, looks like register 16.
When my core is at 756, my voltage reads 1.19v, looks like register 15.

http://www.evga.com/forums/tm.asp?m=...55974;�

My question was: Is my register 17 for shader voltage, or dosen't it work that way?

Posted by Unwinder:
"No, it is not a shader voltage. In serial VID encoding mode (this mode is used on both 4800 and GTX200 series) VT1165 VRM allows generating just one of these 4 voltages defined with registers 15-18 by 2-bit VID defined by state of VRM input pins at the moment on time. Other words, it doesn't allow generating multiple voltages simultaneously and there is no such thing as shader voltage. VRM supports 4 different voltage entries in serial VID mode and your GPU needs only 3 of them (one for 2D, one for Low Power 3D and one for performance 3D mode. So that is just an unused voltage entry".

On my system, register 17 is just an unused voltage entry...

He further confirmed for me that the voltage value: "applies only to GPU core (and stream processors aka shaders, as they are part of GPU). Memory chips are driven by differnt VRM (not software controlable)".

I think that indeed, 1296 is the end of the story for my 280's memory.