Solved Second monitor is not detected after switching to vt and back

[aragats]

This is a desktop system with Nvidia Quadro K2200 running FreeBSD 11.0-STABLE.

The main monitor connected to DVI, the second one to DP. After switching from X to console by pressing Ctr-Alt-Fx the second monitor turns off (I don't care much about it), but when I return back to X it's not detected anymore. Cycling its power or re-plugging the cable doesn't help.

Thanks for advises and directions.

 

[tingo]

Does xrandr detect your second monitor after you have switched back to Xorg? Or is it missing from xrandr's output?

 

[aragats]

No, xrandr didn't show it.
Moreover, restarting X didn't help either!
I did not see anything in logs, however, after restarting X several times I got:

$ dmesg
....
NVRM: GPU at PCI:0000:02:00: GPU-ab938ff1-e040-fb6e-766f-a40885fde38b                                                                                                                                                                         
NVRM: GPU Board Serial Number: 0423416023252                                                                                                                                                                                                 
NVRM: Xid (PCI:0000:02:00): 13, Graphics Exception: Shader Program Header 11 Error                                                                                                                                                           
NVRM: Xid (PCI:0000:02:00): 13, Graphics Exception: Shader Program Header 18 Error                                                                                                                                                           
NVRM: Xid (PCI:0000:02:00): 13, Graphics Exception: ESR 0x405840=0xa0040800                                                                                                                                                                   
NVRM: Xid (PCI:0000:02:00): 13, Graphics Exception: ChID 0008, Class 0000b097, Offset 00000100, Data 0fffcc0

I couldn't restart the machine, so continued working with one monitor. Guess what then? After 4-5 hours the second monitor has been suddenly detected by xrandr (I ran it from time to time)!

 

[tingo]

Do you see an interesting messages in dmesg or /var/log/messages that corresponds with the time that xrandr starting showing your second monitor? Perhaps the nVidia card CPU / engine was hung and got restarted by the driver?
IME, some nVidia cards and / or drivers have problems with more than one monitor; two monitors work, but the way they work are not consistent, that makes them a bit unreliable to work with.
(Or gfx cards / chipsets might have similar issues, but I have less experience with dual monitors on them).

 

[aragats]

Do you see an interesting messages in dmesg or /var/log/messages that corresponds with the time that xrandr starting showing your second monitor?

No, nothing was reported.

I guess, it was a kernel or nvidia driver bug. I've upgraded my system from 11.0-STABLE to 11.1-RELEASE and everything works as expected.