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Could please anybody help me identify what is the source of problem? The problem is that after some time or after opening a window of some application in X, it seems like I suddenly lost 2d acceleration.

Because the process /usr/bin/Xand all its operations ( window resizing, scrolling) suddenly eats 60% to 150% of CPUs runtime when scrolling window for instance.

I'm using twinview, but it happens even without it, but not so much. I'm not using any composition in KDE or xfce.

The nvidia driver installation logs looks there was no problem during the installation.

I tried various different kernel versions, 2 different Xorg version, 2 versions of nvidia driver and even different window managers.

It only happens in particular time frames, if I open some specific www page or application in browser or it comes from nowhere.

It is possible that it could be triggered by some flash animation, gif animation, javascript scrolling text or other effects in browser, but it is really hard to say, because it usually appears suddenly (when reading something in browser for instance).

As far as xorg.conf, I have the default one from nvidia-settings. I also tried various possible configurations and modules.

I have glxgears 2.241 FPS and after the problem is gone I have 6267.623 FPS.

Slackware-current - kernel , , 2.6.36.x 2.6.37
X.Org X Server 1.9.4
KDE 4.5.5   or   xfce-4.6.2
NVIDIA-Linux-x86_64-260.19.36  + twinview
Geforce 8400 GS


XChat 2.8.8
share|improve this question
Yes, that sounds like a bug in the nvidia proprietary driver. Does your card work (even with reduced functionality) with the Nouveau open-source driver? If so, you can run with that for a while to see if the problem occurs, which will help you isolate the issue. – mattdm Mar 6 '11 at 20:57
Is this question still relevant? Does these problems still exist? Both NVidia and Nouveau came a long way since this was asked. – Patkos Csaba Feb 13 '12 at 21:04

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