Comment 4 for bug 1431149

I'm running XUbuntu 15.04 (final release) for a few weeks on my laptop. I did some initial tests directly after I installed it and it worked properly. But unfortunately after a few days the bug occured from time to time. It's not reproducible. I'm using the laptop almost every day and every 4-5 days, the screen remains black after login (after it woke up from standby or hibernation).