I'm running Ubuntu 12.04 on my Lenovo Z570. I've been using it for the past few months and after some initial bugs with wifi and grub, It's been working fine.

Lately, (a few weeks ago) the computer has not been able to "wake up" out of sleep, suspend, or hibernate mode.

If i close the laptop, then open it, the screen turns on and the pointer appears, but it is just a black screen.

If it sleeps by itself because i left it alone too long, the screen turns back on, but the image is just whatever was up when it slept, albeit in the upper left corner the program running is gnome-screensaver, which makes me think it might be a bug with the screensaver, however it could be the actual sleep/hibernate/suspend/wakeup function.

Any ideas on what to do or how to find out more?