Hi,
I'm running a Fedora 13 machine with KDE 4.5.5 on it. Yesterday I upgraded from an nvidia 250 to a new 570. On bootup the graphical login greeted me but after logging in KDE4 didn't fully start. The splash screen was up then the background at proper resolution but no panel. The right click menu was OK and I started a few terminals from there but no windows were displayed. They were running as a alt+tab showed the switcher and the frame of where a window might have been, but no windows were drawn, just the black rectangle. When I thought I had a terminal "selected" I ran nvidia-settings, which again was not shown, but did turn up in the alt+tab menu so I guess was run but unable to be seen or interacted with.

I have tried NVIDIA-Linux-x86_64-260.19.29, NVIDIA-Linux-x86_64-260.19.36, and the beta NVIDIA-Linux-x86_64-270.18 all having the same effect. If I login to a gnome session I get the panel etc fine. If I am devious and startkde after logging in to a gnome session, KDE hangs on start again. If I then force metacity to --replace kwin I can get the KDE panel and windows etc all showing properly.

If anyone has hints as to what options to tweak or where to look to see why KDE doesn't want to startup it would be wonderful. I had a two screen configuration using activities before on the 250. Activities don't work when metacity replaces kwin it seems :/

It appears that KWin is having issues with your graphics card or driver. Try disabling Desktop Effects using System Settings, or press Alt + Shift + F12 to temporarily switch them off.

I tried the hotkey to toggle desktop effects but it didn't seem to make any difference. They hotkey did work in the past with the nvidia 250 card though.

kernel = 2.6.34.7-63.fc13.x86_64
xorg-x11-server-common-1.8.2-4.fc13.x86_64

Though I'm fairly sure that the NVidia closed source drivers negate these two...
mesa-libGL-7.8.2-1.fc13.x86_64
mesa-libGLU-7.8.2-1.fc13.x86_64

there is a 270.26 driver available on the Nvidia ftp site

the 570 is an awfully new card, maybe that's the cause of the problem (though the 260.18 driver lists it as supported)

I also noticed in systemsettings/Desktop Effects/Advanced that I was trying to use Compositing Type=OpenGL. Perhaps using Xrender might work... another thought I had was changing the OpenGL Mode. Unfortunately the toggle composite hotkey didn't help, so I'm a bit sceptical that xrender will help.

The upside is that even though the card was only announced on December 7th, most of the rest of the desktop works fine. The panel and plasma work ok, vdpau etc. It's just really unfortunate that I'm running all this with a different window manager :/

Unfortunately, I broke the golden rule and made many changes at once. But I can now confirm that KDE and kwin work using NVIDIA-Linux-x86_64-270.26.run on a fully updated Fedora 13 machine (kdebase-4.5.5-1.fc13.x86_64). I have turned OpenGL compositing back on and it works too.

For those finding this via the web searchers, I noticed that with two DFP attached on the 250 they were DFP-0 and DFP-1, on the 570 they are DFP-0 and DFP-2. I'm assuming the HDMI will come up as DFP-1 on the 570. Your configuration might be different, but this info might help getting your metamodes working for twinview again.