I have been really annoyed when I change my wallpaper, and my entire system comes to a stand still and lags for about 10 seconds, because of fade effect.

Is there anyway to disable this? It would be greatly appreciated for some help.

I'm on Kubuntu 10.04 LTS Lucid Lynx
my kde version is 4.5.3

Have you tried System settings>Desktop effects>All effects and disabling the Fade options?

yes
I also have these problems when the desktop effects are disabled

any suggestions ?

I can turn off the fading via John's method but I've had no luck finding a setting for the wallpaper display delay. I'm using 4.6 RC2 on Maverick.

Unless you're exaggerating, 10 seconds isn't normal. It should be literally about a second and a half without holding up your entire system. Did this just start with 4.5.3? Are you able to upgrade to 4.5.5 on Lucid?

5 seconds watching a movie
10 seconds playing videogames.
Upgrading to 4.5.5 didn't solve the problem
in kde 4.3 I used to solve this selecting:
systemsettings --> application appearence --> style -->fine tuning --> Low display resolution and low cpu.
But this setting didn't work on kde 4.5.3 !
Do you know where in the .kde folder can I find the configuration file of this setting ?
Thanks for help

First, have you tried disabling Desktop Effects completely to see if that is having any effect? Second, have you tried switching away from Oxygen to Plastique or another style to see if it is that which is causing the slowness?

yes,indeed
but nothing changes
All that I want is switching immediately my wallpapers in slideshow mode ,whithout fade effect from one to another wallpaper
same as in kde 4.3

If anybody knows any kind of solution (recompiling,patching sources) please explain it
could be very appreciated
thanks

Do you still have the same problem? I do... I want to use a slideshow as my desktop background, but everything (youtube, any keyboard input, scrolling in Chromium, etc) freezes and stutters while the wallpaper crossfades.

gentoo ~amd64
KDE 4.6.3
gentoo-sources kernel 2.6.39
nvidia driver 275.09

I tried downgrading to kernel 2.6.35 and nvidia 256.53 - same symptoms.