I have seen in forums and manuals that you have to add
Option "Coolbits" "value"
to xorg.conf or similar files.
I have been able to get this working for the first GPU, the one rendering the display. I have not been able to get overclocking options in nvidia-settings for the second GPU, not rendering any display.
I have tried things like
Section "Device"
Identifier "Videocard0"
Driver "nvidia"
BusID "PCI:2:00:0"
Option "Coolbits" "12"
EndSection
Section "Device"
Identifier "Videocard1"
Driver "nvidia"
BusID "PCI:3:00:0"
Option "Coolbits" "12"
EndSection
in the various files: xorg.conf, 99-nvidia.conf, nvidia-xorg.conf. Everything I have tried has led to black screens, no overclocking capability or overclocking capability on the first GPU only.
Is it possible to unlock overclocking for both GPUs, if so how?
I have not found this question asked anywhere. I am running 346.59 drivers on Fedora 21.
Best Answer
Changing the xorg.conf file to add virtual X servers for each of the cards (even those not connected to a monitor) solved the issue.
Basically, you want to have a server layout section with all of your real and virtual screens:
Then, for each your cards, you can put in (almost) identical "Monitor", "Screen" and "Display" sections, differing only by their identifiers, which in the following are
N
, but should be repaced by the card number,0
,1
, etc. Note that at least the parameters for the real monitor should correspond to what you currently have in yourxorg.conf
file, i.e. in the following I haveCRT
since it's an old VGA monitor.