No display with NVIDIA drivers 5xxx with DVI

[nggalai]

Hi there,

 

took me a while and a couple of e-mails to NV to figure it out, but here's one viable solution for all those people running one screen only, on DVI, who are also required to use the latest slew of nvidia drivers (namely, 5x.xx). The older, very stable 4x.xx branch doesn't interface with kernels 2.6.x, hence this short FAQ.

 

Description

After installing NVIDIA driver set 5336 for Linux, starting X will either produce garbage onscreen, or the digital flat panel goes to sleep mode. Not all Geforce cards are affected, but most newer ones show this issue. The problem only persists if using a DVI flat panel (to be called DFP from here on) on a graphics adapter equipped with both D-Sub (RGB) and DVI connectors. Bootup and BIOS screens appear normal, console appears normal, but startx -> black screen. X appears to be starting quite normal, can be left with CTRL+Alt+Backspace, and the system can be rebooted normally. If the DFP is connected to the standard D-Sub RGB output of the graphics board, X appears just fine.

 

Analysis

NVIDIA switched to a more "Windows"-like drivers setup with the 5xxx "DetonatorFX" branch of drivers. The driver assumes that, if you connect anything to the secondary connector on a VGA, you'll have something on the primary, too. This behaviour could be overruled by using

Option "ConnectedMonitor" "DFP"
Option "IgnoreDisplayDevices" "CRT"

in past incarnations of the driver. This no longer applies due to recent changes in NV's TwinView handling. On a small number of Geforce VGA, it still works with 5336 and no tweaking (namely boards that have customised BIOSes), but generally: no go.

 

The reasons behind it: In the past, "ConnectedMonitor" defined what OUTPUT CONNECTOR to use in X. Now, it (correctly) defines what TYPE of monitor is hooked up to ANY of your VGA's connectors. Windows worked like that for a long time, and probes for connected screens at login. VESA modes and derivates (say, during kernel boot time or when using X's nv driver) work because they "clone" the output to all connectors of the primary graphics board. People with dual head know what I'm talking about--BIOS screens and consoles prior to entering X appear on all screens connected to your primary VGA, simultaneously.

 

Solution

 

1) Enable TwinView in your XF86Config-4, even though you only have one screen connected.

2) Tell the driver you're running TWO DFP displays, both in "clone" mode.

3) Force vertical refresh for the "second" display (i.e. your actual DFP) in the TwinView options.

4) Define screen resolutions in your TwinView options (Screen Section won't be enough).

5) Don't ignore more devices than TV (if applicable).

 

This solution was reproducable a number of times, and is endorsed by NVIDIA. Well, at least by the one NV bloke I know who works for tech support. ;)

 

Sample XF86Config-4 (excerpt)

 

Section "Device"
   Identifier "device1"
   BoardName "NVIDIA GeForce FX 5800"
   Driver "nvidia"
   Option "IgnoreDisplayDevices" "TV"
   Option "NvAGP" "1"
   # Hack for stupid feature in 5336 KILL BRUJO
   Option "TwinView"
   Option "MetaModes" "1600x1200, 1600x1200"
   Option "SecondMonitorVertRefresh" "60"
   Option "TwinViewOrientation" "Clone"
   Option "ConnectedMonitor" "DFP,DFP"
EndSection

Questions, corrections, and remarks are very welcome, of course.

 

93,

-Sascha.rb

Edited March 1, 2004 by nggalai

[Guest baaden]

Hi nggalai,

 

thanks a lot for your email, it was very helpful .. although it did not solve my problem.

I am using the latest nvidias driver version (6629) and have the following problems:

- console mode with DVI connection is ugly (flashing red dots, unstable display)

- X11 up to 1280x1024 via DVI is perfectly fine

- any higher resolution with DVI leads to flickering (looks like an unstable frequency from

the card that makes the monitor think the resolution has changed and triggers auto-adjustment

which makes the screen blank for a seconf)

- Using VGA connection to my flatpanel, everything is fine and works up to 1600x1200

 

I have tried your settings for XF86COnfig-4, but to no avail.

 

Any further hints are greately appreciated.

 

Could you send me the names/emails of the guys you contacted at NV support ?

 

Very best wishes and thanks in advance,

MB