SUSE Linux Enterprise Desktop Screen going blank at odd times

SUSE Linux Enterprise Desktop 10 Service Pack 1
SUSE Linux Enterprise Desktop 10

While running SUSE Linux Enterprise Desktop, the screen appears to go into screen saver mode (i.e. the screen goes blank).  This occurs even though the screen saver has been disabled.

This problem can be related to DPMS (Display Power Management Signaling for the monitor) with certain versions of the nVidia proprietary driver and certain models of nVidia graphic adapters.  To determine if this is the case in your environment do the following:

1.  Open a terminal window and type su to login as root
2.  type hwinfo --gfxcard

In the output that appears look for the following lines towards the bottom:

  Driver Info #0:
    XFree86 v4 Server Module: nvidia
  Driver Info #1:
    XFree86 v4 Server Module: nvidia

If those lines contain anything other than nvidia the resolution explained in this TID does not apply to your situation.

The problem can be resolved in 1 of 2 ways.  The first is to switch back to the open source driver for the nvidia cards (i.e. the "nv" driver).  This can be accomplished by doing the following:

       1.  Open a terminal window and type
                        init 3 
                (NOTE: this will shutdown the graphical desktop so be sure to save and exit any applications before executing init 3).
       2.  login as root when prompted
       3.  type the following to switch to the open source driver
                   sax2 -r -m 0=nv
            (NOTE: the 0 following the -m is a numeric zero and not an uppercase O.  Also, this command assumes you have only 1 graphic adapter installed).
       4.  Run through the sax configuration verifying that the card, monitor, and specified resolution are correct. Then exit and perform a "test" when the option appears.
       5.  When returned to the command line type
                   init 5
The system will return to the graphical desktop and the screen blanking should not continue.  While this option provides relief it also removes the XGL functionality, so it may not be the preferred option.

The second option is to disable DPMS.  The steps to do that are as follows:

1.  Edit the /etc/X11/xorg.conf file
2.  Scroll down until you locate the "monitor" section which should look something like this:
            Section "Monitor"
              Option       "CalcAlgorithm""XServerPool"
              DisplaySize  380 300
              HorizSync    30-81
              Identifier   "Monitor[0]"
              ModelName    "1908FP"
              Option       "DPMS"
              VendorName   "DELL"
              VertRefresh  56-76
              UseModes     "Modes[0]"
            EndSection
3.  Edit the line containing Option "DPMS" so that it reads the following:
             Option "DPMS""off" 
4.  Save and exit.
5.  Open a terminal window and type su to login as root
6.  Type
          xset -dpms
7.  Close the terminal window and reboot the machine.

Both of the options applied together will disable the DPMS functionality and should resolve the screen blanking issue.