I'm adding this comment to document my own experience that I resolved myself just to provide another datapoint.
I was running 9.04 with proprietary Nvidia drivers with rebuilds done with DKMS (but installed via Ubuntu restricted drivers as fas as I can recall, nothing done by hand). After upgrade 9.10 could no longer compile the drivers with DKMS. Reverting from "nvidia" to "nv" in xorg.conf would fix things. It was disappointing that when X failed to start Ubuntu didn't automatically fall back into some safe mode which I've seen distros (including Ubuntu I believe) do before. The problem with DKMS was that I was using a -i386 kernel, not -generic (linux-image-386 vs linux-image-generic). However, the wrong headers were installed (linux-headers-generic instead of linux-headers-386). Once I installed linux-headers-386 DKMS was able to build the nvidia driver and I was able to switch my xorg.conf back. I can imagine than a non-technical user would have been hopeless to debug or resolve this. Myself, I'm not sure what happened with 386 vs generic for the my kernel. I don't remember what I ran before in 9.04 but I don't recall manually choosing such a thing before. I append my /proc/cpuinfo before. One off the top of my head theory is somehow during the upgrade either my kernel was switched from -generic to -i386 or my headers were switched from -i386 to -generic or some "unnecessary" package was removed (linux-headers-386) even thought it was needed to compile nvidia with DKMS... processor : 0 vendor_id : GenuineIntel cpu family : 6 model : 8 model name : Pentium III (Coppermine) stepping : 6 cpu MHz : 996.663 cache size : 256 KB fdiv_bug : no hlt_bug : no f00f_bug : no coma_bug : no fpu : yes fpu_exception : yes cpuid level : 2 wp : yes flags : fpu vme de pse tsc msr pae mce cx8 mtrr pge mca cmov pse36 mmx fxsr sse up bogomips : 1993.32 clflush size : 32 power management: -- upgrade breaks graphic drivers and x, preventing login or startx https://bugs.launchpad.net/bugs/464591 You received this bug notification because you are a member of Ubuntu-X, which is subscribed to xorg in ubuntu. _______________________________________________ Mailing list: https://launchpad.net/~ubuntu-x-swat Post to : ubuntu-x-swat@lists.launchpad.net Unsubscribe : https://launchpad.net/~ubuntu-x-swat More help : https://help.launchpad.net/ListHelp