screen flickers

[jeet]

I have xubuntu Hardy Heron and this problem was there with previous install of Gursy also. The problem is that I frequently see flicker on screen. To be more precise I see and rapid switching of desktop switching between the four virtual desktops. Some times it stops by itself and other times I have to resort to ctrl-alt-backspace. I have Dell 1905fp LCD monitor and I have update horizSync and VerRefresh rate in xorg.conf. Here is relevant portion of my xorg.conf,

Section "Device"
Identifier "Trident Microsystems CyberBlade/i1"
Driver "trident"
BusID "PCI:1:0:0"
EndSection

Section "Monitor"
Identifier "Generic Monitor"
Option "DPMS"
HorizSync 31-80
VertRefresh 56-75
EndSection

Section "Screen"
Identifier "Default Screen"
Device "Trident Microsystems CyberBlade/i1"
Monitor "Generic Monitor"
DefaultDepth 24
EndSection



How can I fix this problem?

-Navjeet