KDE sluggish after extended usage

[unchiujar]

I use KDE with transparency enabled and after a certain amount of usage it starts to get slow, applications take 30s-1m to start (where before they were instantaneous), and sometimes transparency effects lag. There is no processor or memory usage increase to justify this effect. This problem disappears if I restart X and appears again after using KDE after a while. Also, I didn't have this problem before enabling translucency.
My video card is a

 00:02.0 VGA compatible controller: Intel Corporation Mobile 945GM/GMS/940GML Express Integrated Graphics Controller (rev 03)

Any ideas what might be causing this ? It's more of a nuisance than a problem but I would like to fix it.

[devils casper]

Which Distro do you have? Post the Video Card and Screen Sections of /etc/X11/xorg.conf file.

[unchiujar]

I'm using Gentoo with an external monitor from time to time and my xorg is setup for dual head with and w/o xinerama and for single (only laptop lcd) use.
xorg.conf

 
Section "Device"
    Identifier  "** Intel i810 (generic)               [i810]"
    Driver      "i810"
    VideoRam    131072
    #=========== DISABLE FOR POWERSAVING ===============
    #Option "NoDRI"  "true"
    Option      "DRI"     "true"
    # Insert Clocks lines here if appropriate
    BusID  "PCI:0:2:0"
    Option "RenderAccel" "true"
    Option      "MonitorLayout" "CRT,LFP"
    Screen 0
EndSection

Section "Device"
    Identifier  "Monitor-i810"
    Driver      "i810"
    VideoRam    131072
    Option      "DRI"     "true"
    Option "RenderAccel" "true"
    #Option "NoDRI"  "true"
   BusID  "PCI:0:2:0"
   Screen 1
   Option "MonitorLayout" "CRT,LFP"
EndSection



Section "Screen"
    Identifier  "Screen 0"
    Device      "** Intel i810 (generic)               [i810]"
    Monitor     "LappyPanel"
    DefaultDepth 24

    Subsection "Display"
        Depth       8
        Modes       "1280x1024" "1024x768" "800x600" "640x480"
        ViewPort    0 0
    EndSubsection
    Subsection "Display"
        Depth       16
        Modes       "1280x1024" "1024x768" "800x600" "640x480"
        ViewPort    0 0
    EndSubsection
    Subsection "Display"
        Depth       24
        Modes       "1280x800" "1280x1024" "1024x768" "800x600" "640x480"
        ViewPort    0 0
    EndSubsection
EndSection


Section "Screen"
    Identifier  "Screen 1"
    Device      "Monitor-i810"
    Monitor     "Sceptre"
    DefaultDepth 24

    Subsection "Display"
        Depth       8
        Modes       "1440x900" "1280x1024" "1024x768" "800x600" "640x480"
    EndSubsection
    Subsection "Display"
        Depth       16
        Modes       "1440x900" "1280x1024" "1024x768" "800x600" "640x480"
    EndSubsection
    Subsection "Display"
        Depth       24
        Modes       "1440x900" "1280x800" "1280x1024" "1024x768" "800x600" "640x480"
    EndSubsection
EndSection

Section "ServerLayout"
# The Identifier line must be present
    Identifier  "Single"
    Screen 0 "Screen 0"
#    InputDevice "Mouse1" "CorePointer"
#============ DISABLE SYNAPTICS FOR POWERSAVING =============
    InputDevice "TouchPad" "AlwaysCore"
    InputDevice "Keyboard1" "CoreKeyboard"
    Option      "AIGLX" "true"

EndSection


Section "ServerLayout"

# The Identifier line must be present
    Identifier  "Dual"
    Screen 0 "Screen 0"

    Screen 1 "Screen 1" RightOf "Screen 0"
#    InputDevice "Mouse1" "CorePointer"
#============ DISABLE SYNAPTICS FOR POWERSAVING =============
    InputDevice "TouchPad" "AlwaysCore"
    InputDevice "Keyboard1" "CoreKeyboard"
    Option      "AIGLX" "true"

EndSection


Section "ServerLayout"

# The Identifier line must be present
    Identifier  "DualXinerama"
    Screen 0 "Screen 0"
    Screen 1 "Screen 1" RightOf "Screen 0"
    Option "Xinerama" "On"
#    InputDevice "Mouse1" "CorePointer"
#============ DISABLE SYNAPTICS FOR POWERSAVING =============
    InputDevice "TouchPad" "AlwaysCore"
    InputDevice "Keyboard1" "CoreKeyboard"
    Option      "AIGLX" "true"

EndSection


Section "DRI"
    Group 0
    Mode 0666
EndSection

Section "Extensions"
        Option         "Composite"   "Enable"
EndSection

I also use 915resolution to set the appropriate values in the video BIOS so I can use the 1440x800 monitor and the laptop at 1280x800. The 640x480 is for playing Starcraft fullscreen

Intel 800/900 Series VBIOS Hack : version 0.5.3

Chipset: 945GM
BIOS: TYPE 1
Mode Table Offset: $C0000 + $269
Mode Table Entries: 36

Mode 30 : 1280x800, 8 bits/pixel
Mode 32 : 800x600, 8 bits/pixel
Mode 34 : 1024x768, 8 bits/pixel
Mode 38 : 640x480, 8 bits/pixel
Mode 3a : 1600x1200, 8 bits/pixel
Mode 3c : 1440x900, 8 bits/pixel
Mode 41 : 1280x800, 16 bits/pixel
Mode 43 : 800x600, 16 bits/pixel
Mode 45 : 1024x768, 16 bits/pixel
Mode 49 : 640x480, 16 bits/pixel
Mode 4b : 1600x1200, 16 bits/pixel
Mode 4d : 1440x900, 16 bits/pixel
Mode 50 : 1280x800, 32 bits/pixel
Mode 52 : 800x600, 32 bits/pixel
Mode 54 : 1024x768, 32 bits/pixel
Mode 58 : 640x480, 32 bits/pixel
Mode 5a : 1600x1200, 32 bits/pixel
Mode 5c : 1440x900, 32 bits/pixel

[unchiujar]

Anyone, any clues ?