To all us temporarily poor folk using ancient hardware,
Independently wealthy and/or advanced "world beater
" level probem solvers ...
After a great deal of time, testing and effort, I found the solution for getting the old NVidea cards to not break the display when using the Nouveau driver. There are (to me) a great number of overly complicated and unreliable "solutions" in various places (the often helpful Ubuntu forums, Wiki and such come to mind). I had all but given up hope of trying to get my GeForce4 series card to work acceptably well (of course, forget 3D acceleration -- just working tolerably well, otherwise) under ANY driver -- Nouveau giving the best performance IF
you can get it to work at all. The answer is:
Add nodkmsboot to kernel boot options line!