Comment 104 for bug 1283938

Experienced this problem on a Lenovo Y530 and an Acer Aspire 8943G-9319 after upgrade to 14.04. I am using XFCE flavor of Xubuntu on both. To resolve this problem I disabled Light Locker on both and let XFCE lockscreen take care of the screen locking tasks.

No more black screen after opening lid and logging in.