Re: 8174 hangs my laptop on starting X
OK, I tried the recommendations in post#13, without success.
I uninstalled the old (7676) driver first. The only bits left after that were /usr/lib/libGLcore.so.1.0.xxxx, /usr/lib/libGL.s0.1.0.xxxx and /usr/lib/tls/libnvidia-tls.so.1.0.xxxx files, which all previous drivers seem to leave. I removed them in any case. I ran the 8174 installer, and it completed without error. I ran a followup --sanity check and there were no problems. I could manually modprobe the nvidia module without error.
Attempting to start X with the suggested changes in post #13 resulted in no usable modes. I never needed options in /etc/modprobe.conf, but I tried cycling through the NVreg_Mobile values (unloading and re-loading the nvidia module each time of course); 1,3,4,5 reported no usable modes, while 2 caused the hang/CPU loop. I tried both with NVreg_SoftEDIDs=0 and without it; no change.
I reverted to 7676 (no /etc/modprobe.conf options), and everything works. The bug report is attached for when I was trying without NVreg_SoftEDIDs=0 and with a NVreg_Mobile set to a value that caused a 'no modes' error. I can't get an xorg.0.log of the hang, because the file is not created (or more likely it gets reverted by ext3 journalling because I have to power-cycle the machine).