NVS 510 outputs swapped

Graphics / Linux Linux
1

Hi,

In a previous hardware setup we used two NVS 300’s or 310’s to drive 3 or monitors. That setup was working correctly. Now that we swapped the cards for two NVS 510’s to be able to drive 6 to 8 monitors, the outputs are swapped in pairs. We’re using the same Xinerama based xorg.conf, but only adapted to the new number of screens.

The nvidia settings utility shows the correct order of the displays:

GPU-0_DFP-0, GPU-0_DFP-1, GPU-0_DFP-2, GPU-0_DFP-3, GPU-1_DFP-0, GPU-1_DFP-1

But the output on the monitors is as following:

Monitor 2, Monitor 1, Monitor 4, Monitor 3, Monitor 6, Monitor 5

The monitors are connected to the cards in the correct order. The BIOS post screen and the Linux console are on Monitor 1 as expected.

This configuration has been tried with the 304.60 driver but also version 310.32.

Can someone explain what’s going on here?

2

I have solved the problem. The key is to use the right syntax in the Screen section:

Section “Screen”
Identifier “Screen0”
Device “Device0”
Monitor “Monitor0”
DefaultDepth 24
Option “NoLogo” “1”
Option “metamodes” “DFP-1: nvidia-auto-select +0+0”
SubSection “Display”
Depth 24
EndSubSection
EndSection

Section “Screen”
Identifier “Screen1”
Device “Device1”
Monitor “Monitor1”
DefaultDepth 24
Option “NoLogo” “1”
Option “metamodes” “DFP-0: nvidia-auto-select +0+0”
SubSection “Display”
Depth 24
EndSubSection
EndSection

Notice the swapped DFP-X values compared to the ScreenY/DeviceY/MonitorY values.

Looking back, this problem may also have been present with the NVS 3x0 cards, but because these cards only have two outputs the problem wasn’t as evident as with four outputs.

I hope this saves someone else some time :-)

Gerben