Another thing to try:

1. Boot into setup and turn off all power savings options.
2. Go into control panel and display settings and do the same. set the screensaver to "none"

http://www.ewido.net/en/
http://www.emsisoft.com/en/software/free/

Download those, install them, update them.Then reboot into safe mode and run them. Let them delete abnything that they find.