Ubuntu
xorg package

gnome-display-properties shows wrong refresh rate

Bug #222516 reported by Spencer Paul French on 2008-04-26

This bug report is a duplicate of: Bug #92599: Incorrect (low/stuttering) refresh rate with NVIDIA driver. Edit Remove

Affects		Status	Importance	Assigned to	Milestone
	xorg (Ubuntu)	Invalid	Low	Unassigned

Bug Description

Binary package hint: gnome-control-center

On Hardy Final with the nvidia binary driver gnome-display-properties shows my choice of refresh rates as 50 and 51, even though 50 sets my monitor to 60 and 51 sets it to 75 which are the correct settings.

Revision history for this message

Sebastien Bacher (seb128) wrote on 2008-04-27:

thank you for your bug report, could you run the xrandr command on copy the log to the bug? what videocard and driver do you use?

Changed in gnome-control-center:
assignee:	nobody → desktop-bugs
importance:	Undecided → Low
status:	New → Incomplete

Revision history for this message

Spencer Paul French (spf) wrote on 2008-04-27:

xrandr.log Edit (868 bytes, text/plain)

I have a 7600gt and am using the nvidia binary driver.

Revision history for this message

Sebastien Bacher (seb128) wrote on 2008-04-27:

the xrandr has the same values, the issue is not specific to the GNOME tools, reassigning to xorg

Changed in gnome-control-center:
assignee:	desktop-bugs → nobody

Revision history for this message

Chris Coulson (chrisccoulson) wrote on 2008-07-03:

Thank you for taking the time to report this bug and helping to make Ubuntu better. After reviewing your bug description, I don't think this is a bug. The NVIDIA binary drivers misreport the display resolution, and this is known and documented by NVIDIA in /usr/share/doc/nvidia-glx-new/README.txt.gz:

"Q. Why is the refresh rate not reported correctly by utilities that use the
XRandR X extension (e.g., the GNOME "Screen Resolution Preferences" panel,
`xrandr -q`, etc)?

A. The XRandR X extension is not presently aware of multiple display devices
   on a single X screen; it only sees the MetaMode bounding box, which may
   contain one or more actual modes. This means that if multiple MetaModes
   have the same bounding box, XRandR will not be able to distinguish between
   them.

   In order to support DynamicTwinView, the NVIDIA X driver must make each
   MetaMode appear to be unique to XRandR. Presently, the NVIDIA X driver
   accomplishes this by using the refresh rate as a unique identifier.

You can use `nvidia-settings -q RefreshRate` to query the actual refresh
rate on each display device.

This behavior can be disabled by setting the X configuration option
"DynamicTwinView" to FALSE."

The consequence of this is that the resolution is reported as being between 50Hz and 55Hz, when the monitor is actually being refreshed at the correct rate.

Because of this, I am going to mark this bug as Invalid. If you feel you are still having problems, please reopen the bug by changing the status to 'New', and attach your X server log file (/var/log/Xorg.0.log) to this bug report as an uncompressed attachment. In this case, also please try running with dynamic twinview disabled as per the NVIDIA documentation.

Thank you