"You may have a bad update in your midst. Shut it down again and this time unplug the computer entirely for one full minute. Plug it back it and see if that reset it. Are your keyboard and mouse wireless? You may have to push the CONNECT buttons on both of them and the docking unit to reestablish the connection.
If you get them working hit F8 and go to USE LAST KNOWN GOOD CONFIGURATION. I hope that you had your System Restore points turned on. If not, try SAFE MODE.
On your desktop right click:
1. Properties
2. Screensaver
3. Power
4. At the bottom of the window:
System Standby: NEVER
Hibernation: NEVER
This will prevent power save mode in the future. You don't need it unless you're running a laptop or have a CRT monitor. LCD screens do not burn so easily."