I started experiencing this when a tech installed a new LCD on my mini 10. Just thought I would add this to the thread because this NEVER happened, not even once until he installed a new LCD.
I ordered a refurbished mini 10 from the Dell Outlet. It was supposed to have the 1366x768 screen but it came with 1024x576. A tech came out to my house to install a new LCD panel (actually was a whole assembly with the color backing and antennae). After he left, I shut down the computer and it froze and does this every single time ever since.
So my contribution to this thread is I think it has to do with the video driver.