Comment 11 for bug 800140

I'm experiencing similar problems with an Radeon HD 6700 graphics card: After resuming, I see the mouse pointer, but the unlock screen does not appear. In fact, it seems to be rather invisible but still active, as I am able to enter my password and unlock the screen blindly.

Switching to an text console, playing with xrandr and switching back results in screen corruption. Killing the X server with sysrq-k brings back an lightdm login screen (but obviously kills my session).