Another symtem to add: I have been getting long seequences where it boots only into low graphics mode. (5 or 6 boots in a row). I have not had the patience to see if it would eventually recover on its own, but booting with my second monitor (HDMI) disconnected seems to exit the sequence. Once booted, I can re-connect the HDMI monitor and the system will automatically detect & enable the second monitor.
Another symtem to add: I have been getting long seequences where it boots only into low graphics mode. (5 or 6 boots in a row). I have not had the patience to see if it would eventually recover on its own, but booting with my second monitor (HDMI) disconnected seems to exit the sequence. Once booted, I can re-connect the HDMI monitor and the system will automatically detect & enable the second monitor.