Undervolting GTX280 - The Way To Be Cool!
Be careful, you are loosing your guarantee!
Everytime use your own original Bios for modding!
If the flashing is going wrong and you have a black screen, you can use a pci-graphic card for flashing the GTX280 again or keep the steps in mind and blind-type the commands!
What u need:
Download: Nibitor 4.2
Download: GPU-Z 0.2.4
If You cant read out the Bios of your card with Nibitor, use GPU-Z and save the file then open it with nibitor.
Change the "EXTRA" voltage (in the pic below) from 1.18v down to 1.06v and save the file. I recommend to use 1.06v cause 1.03v could not be good in overclocking the card. With 1.03v the system freezes over 665MHz.
The "3D" clock ist 1.06v at stock, you can set it down to 1.03v.
Anytime, if you´re getting freezes, raise the EXTRA voltage from 1.03v to 1.06v for example.
Save nvflash.exe, the original and modded biosfile on the dos-start-disk and boot from the floppy disk.
Type during the dos screen "nvflash.exe -5 -6 biosfile.rom" - confirm with "y" and the flashing is done.
With my Point of View GTX280@ 1.03v, only 655/1410/2430 are stable instead of 700MHz with 1.18v, but its much cooler and more quiet.
1.06v (3D) now 1.03v
1.18v (Extra) now 1.03v
380Watt vs. 320 Watt!!! > ~60Watt
I need only 320W at maximum, witch was 380W bevore flashing, thats incredible.
Test (25° celsius room temperature)
GTX280 - 1.18v
88° - 100% fan
78° - 61% fan (down to 68° Grad with 100%)
GTX280 - 1.18v
~82° - ~80% Lüfter
~72° - ~51% Lüfter
It doesnt matter which game, the fan is not faster than 1080rpm/61%!!
In Crysis, Age of Conan, Assassins Creed, Jericho the Fan is mostly about 50%, 72-76°, and ~280W, thats amazing!
The Card is absolutely silent in 2D with the Fan at 25%. Rivatuner is managing the Fan by itself and only if the GPU Temp is getting over 65° celsius the fan ist moving from 25% to auto. (you have to create oc and fan profiles in rivatuner!)
In idle, the GPU is about 55° celsius and 25% fan (25° room temperature)
OC with less Volt? SURE!!
With 1.03v under load, i can manage 655/1410/2430
I played Crysis, Age of Conan, Assassins Creed, Jericho for about 12h and the card was absolutely stabel, even in Benchmarks (3Dmark/Furmark)