I am running Debian Etch/Testing and using the xserver-xorg-video-nv driver for my (relatively new) graphics card - a Gainward Bliss 7300LE.
The display is, in general use, perfectly acceptable but when restoring the screen after the screensaver has blanked it or switching back from a text console to the X display I sometimes get a very peculiar effect.
It is almost as if parts of the display appear as a negative - white becomes black, yellow becomes blue etc. Any text appears very broken to the point that it is illegible. This only affects parts of some areas of colours i.e. an area of yellow will appear blue in the top half but yellow in the bottom half but another area of white will appear black all over. Have you ever seen a little Tux with green feet?
If I then switch to a text console and then back to the X display it nearly always rights itself although sometimes two or more switches are necessary.
It cannot be produced on demand. Switching consoles sometimes has no detrimental effect.
Can anyone suggest a reason for this and, hopefully, a cure?