Please install 260.19.06-ubuntu1 again, reboot and reproduce the crash. Then save your /var/log/Xorg.0.log, your /var/log/Xorg.0.log.old and dmesg in recovery mode and switch back to the driver that works for you. Finally attach the 2 logs.
The attached X log and dmesg are about 256.53 therefore I can't see the error.
Please install 260.19.06-ubuntu1 again, reboot and reproduce the crash. Then save your /var/log/ Xorg.0. log, your /var/log/ Xorg.0. log.old and dmesg in recovery mode and switch back to the driver that works for you. Finally attach the 2 logs.
The attached X log and dmesg are about 256.53 therefore I can't see the error.