The main culprit with the latest "x11-driver-video-nvidia-current 260.19.29-1" - package seems to be:
Enabling 3d-Desktop effects !!!!!!!!!!!!!!!!!!! This definitely ends up with a malfunction of my graphics ( see my original posting ).
Running "drakx11" in a Terminal, reconfiguring my graphics with DISABLING compositing ( 3D-effects ), then restarting the system, and almost everything goes well again, except for, you guess, those 3D-effects.....
And, by the way, I also tested this with LinuxMint 10. Downloading and installing the proprietary-drivers resulted in exactly the same problem: No graphics after a reboot....
Even trying to start the latest PCLOS 201.12 livecd ends up this way. "No input signal" on STRG-CTRL-F8 and of course a Konsole on STRG-CTRL-F1 !!
Is COMPOSITING enabled by default
The only way to get started is with the VESA-drivers.
I wonder if this is just a problem with my GeForce 8400 GS or other Nvidia cards, too !?
Greetings and a really happy, succesful and healthy New Year to you all....