Disable "detect refresh rate" for nVidia drivers

Bug #145431 reported by Dennis Schmitz on 2007-09-27
This bug affects 3 people
Affects Status Importance Assigned to Milestone
compiz (Ubuntu)

Bug Description

Binary package hint: compiz-gnome

If nvidia driver (nvidia-glx-new 100.14.19) is activated through restricted-manager compiz starts after a restart which works quite good...
BUT, it is slow because it could be configured better!

There's a bug in nvidia driver which reports refresh rate values wrong to other apps (e.g. displayconfig-gtk or compiz, etc...) #92599
So compiz only uses 50 frames but it should use 60 or 70 fps! Detect Refresh rate makes everything even worse...

It would be nice if 'detect refresh rate' is disabled and compiz refresh rate is set to 60Hz or to an even higher setting to prevent stuttering.

regards Dennis

Changed in compiz:
importance: Undecided → Low
status: New → Confirmed
Dennis Schmitz (deezid) wrote :

Thanks for confirming :)
Anyway, it's a small "bug". ;)

regards Dennis

Dennis Schmitz (deezid) wrote :

I've noticed that 'sync to vblank' is now disabled with the latest compiz release.
Why? It looks ugly without when moving windows and isn't any faster!

Sync to vblank is a must and detect refresh rate has to be disabled (when nvidia rendering is used) since things get much worse with it.
Plus the hz rate has to be set to an higher value to prevent stuttering.

Please test it yourself before the release!
regards Dennis

Olivier Cortès (olive) wrote :

On my x86_64 machine (latest Hardy), enabling "sync to vblank" makes compiz really slow. disabling it is way much smoother.

teedog (teedog) wrote :

I can confirm this problem with the latest nvidia-glx-new and nVidia 6200 TurboCache.

Why is this considered a small bug? It's critical in my opinion because it effectively cripples a new Ubuntu installation once the user enables the restricted nVidia drivers, which is recommended. Once restricted drivers are installed, 3D desktop effects are immediately enabled by default. This slows the system to a crawl, and seems to make many windows appear blank, like the Preferences/Appearance window, so one cannot disable 3D desktop effects. The only way is to disable the restricted nVidia drivers. Non-savvy users would not know what to do most probably.

Travis Watkins (amaranth) wrote :

You are apparently having a different problem. The bug here is that compiz is running at 50fps instead of 60fps. It's not that much slower, just annoying. If nvidia would not do crazy things with their driver this problem would not exist.

Pedro Villavicencio (pedro) wrote :

Thank you for taking the time to report this bug and helping to make Ubuntu better. You reported this bug a while ago and there hasn't been any activity in it recently. We were wondering is this still an issue for you? Could you try to reproduce the same with Ubuntu 9.04? Thanks in advance.

Changed in compiz:
status: Confirmed → Incomplete
Dennis Schmitz (deezid) wrote :

Everything is still the same, nothing has changed :(
- 50hz
- detect refresh rate
- no vsync (heavy tearing!)


summary: - compiz slow with nvidia
+ Disable "detect refresh rate" for nVidia drivers
Changed in compiz (Ubuntu):
importance: Low → Wishlist
status: Incomplete → Triaged
Dennis Schmitz (deezid) wrote :

I will test the next alpha then.
The current Builds don't start here (kernel panic...).

Will SyncToVBlank be enabled? (Kwin4 does this, too. Looks as smooth as Vista/7 or OSX then!)

PS: Mplayer/Xine/VLC etc... should be compiled with vdpau support!
Vdpau does an incredible job.

FullHD 1080p/24p - smooth, no tearing with kwin4 compositing!
SD 576i/25i - 50 pictures/s (with bobbing), still no tearing :D

regards Dennis

Dennis Schmitz (deezid) wrote :

Tested with nvidia 185.18.14

Travis Watkins (amaranth) wrote :

We'll try enabling sync_to_vblank again for lucid and see if it causes any problems. Too late to do this for karmic.

Vincent Tschanz (fogia) wrote :

sync_to_vblank is still not activated by default in Lucid
refresh_rate must be at least @ 60Hz

The 50Hz and no vsync bydefault is a non sense and contribute to a bad user experience with tearing.
This also affects Video playback where vsync is very important.

Travis Watkins (amaranth) wrote :

Enabling sync to vblank still causes problems for some cards/drivers so could not be enabled by default. We aren't setting 50Hz as the default, compiz is showing you what it automatically detected from your nvidia driver. It gets 50Hz because nvidia abuses the refresh rate value to have a unique identifier for different twinview setups.

oranges (oranges10e) wrote :

Hey guys, has this been looked at for 10.04?

I think this is a very critical problem, too. I have had like 25 ppl try Ubuntu out and most of them go nutts, when the prop. drivers are suggested, installed and the tearing begins. There has to be SOMETHING you can do about this.

ATI released a new driver, with experimental support for Vsync on the desktop. My little Intel GMA 950 puppy does Vsync @default with Compiz just fine on every single thing I throw at it (videos, desktop, games and so on), but for a few YEARS now this has been a prob. with Nvidia cards.

Honestly, I really don't care WHY or WHO; PLEASE just fix it, it's annoying as hell and drivers a lot of ppl nutts, giving Ubuntu a bad rep. for feeling all teary, buggy and trying to fix it. Needles to say, that most of them give up after weeks of trying. It's bad enough, that Plymouth looks ugly with Nvidia prop. drivers and causes all kinds of flickering and other probs, at least get the desktop right.

I don't mean to be rude, but maybe just calling Nvidia or talking to AaronP would help at least a BIT here.


Thank you for taking the time to report this bug and helping to make Ubuntu better. This particular bug has already been reported and is a duplicate of bug 92599, so it is being marked as such. Please look at the other bug report to see if there is any missing information that you can provide, or to see if there is a workaround for the bug. Additionally, any further discussion regarding the bug should occur in the other report. Feel free to continue to report any other bugs you may find.

To post a comment you must log in.
This report contains Public information  Edit
Everyone can see this information.

Other bug subscribers