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obviously (my) Ubuntu has problems with the x window system. Every time when I move any window, this window looks rough and choppy on the edges (see First of all, I though it's a compiz problem ( but obviously it's related to the x window system. I have had this problem since Ubuntu 9.10 and now it's getting annoying. I switched back to nv driver instead of nvidia but no difference. I tried to change the refresh rate, but I can't generate a modeline above 61Hz (because of the LCD's limit). Obviously that's not the problem. Then I tried to set in xorg.con +vsync -hsync and contrariwise but no changes.
I wonder which setting leads to such a behaviour. Is there some kind of antialiasing parameter to set anywhere in xorg? Or is there some kind of "sync to vblank" like in 3D settings? When I move the windows, it looks like an appearing white background for a split second. I can recognize that phenomenon even better when I move a window above another window, especially above the dark brown menu bar. I tried to record that behaviour with mydesktoprecord but ironically you would not see any rough and choppy in this record.

Any suggestions?

Here is my xorg.conf

Section "ServerLayout"
 Identifier     " Configured"
 Screen         0 "Screen0" 0 0
 InputDevice    "Mouse0" "CorePointer"
 InputDevice    "Keyboard0" "CoreKeyboard"

Section "Files"
 ModulePath   "/usr/lib/xorg/modules"
 FontPath     "/usr/share/fonts/X11/misc"
 FontPath     "/usr/share/fonts/X11/cyrillic"
 FontPath     "/usr/share/fonts/X11/100dpi/:unscaled"
 FontPath     "/usr/share/fonts/X11/75dpi/:unscaled"
 FontPath     "/usr/share/fonts/X11/Type1"
 FontPath     "/usr/share/fonts/X11/100dpi"
 FontPath     "/usr/share/fonts/X11/75dpi"
 FontPath     "/var/lib/defoma/x-ttcidfont-conf.d/dirs/TrueType"
 FontPath     "built-ins"

Section "Module"
 Load  "glx"
 Load  "dbe"
 Load  "record"
 Load  "dri2"
 Load  "dri"
 Load  "extmod"

Section "InputDevice"
 Identifier  "Keyboard0"
 Driver      "kbd"

Section "InputDevice"
 Identifier  "Mouse0"
 Driver      "mouse"
 Option     "Protocol" "auto"
 Option     "Device" "/dev/input/mice"
 Option     "ZAxisMapping" "4 5 6 7"

Section "Monitor"
 Identifier   "SamsungSyncMasterP2770"
 HorizSync    30-75
 VertRefresh  56-61
 Modeline "1920x1080@60" 182.28 1920 1952 2640 2672 1080 1102 1113 1135 -HSync +VSync

Section "Device"
        ### Available Driver options are:-
        ### Values: <i>: integer, <f>: float, <bool>: "True"/"False",
        ### <string>: "String", <freq>: "<f> Hz/kHz/MHz",
        ### <percent>: "<f>%"
        ### [arg]: arg optional
        #Option     "SWcursor"            # [<bool>]
        #Option     "HWcursor"            # [<bool>]
        #Option     "NoAccel"             # [<bool>]
        #Option     "ShadowFB"            # [<bool>]
        #Option     "UseFBDev"            # [<bool>]
        #Option     "Rotate"              # [<str>]
        #Option     "VideoKey"            # <i>
        #Option     "FlatPanel"           # [<bool>]
        #Option     "FPDither"            # [<bool>]
        #Option     "CrtcNumber"          # <i>
        #Option     "FPScale"             # [<bool>]
        #Option     "FPTweak"             # <i>
        #Option     "DualHead"            # [<bool>]
 Identifier  "Card0"
 Driver      "nv"
 BusID       "PCI:1:0:0"

Section "Screen"
 Identifier "Screen0"
 Device     "Card0"
 Monitor    "SamsungSyncMasterP2770"
 DefaultDepth 24
 SubSection "Display"
  Viewport   0 0
  Depth     1
share|improve this question
And the GPU is? – Aki Dec 12 '10 at 19:49
It's NVIDIA Geforce GTS 250. – Bevor Dec 12 '10 at 20:41

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