You find others with this issue.
Try the usual cleaning noted at http://forums.cnet.com/5208-19681_102-0.html?messageID=3196452&tag=forums06;posts#3196452 and if that doesn't help, install the OS from the restore media and if that fails get a quote for a new motherboard.
Bob
My laptop works fine most of the time, except for 2 things. When the computer does an automatic shut down or after I've been using it for several hours, if I try to get back on after less than 2 hours or so, I have 2 giant opaque horizontal boxes which cover the bottom 2/3rds of the screen. I first had this happen when my computer went into sleep mode. I eventually had to totally shut-off sleep mode because it would do this every time. I've tried updating the display driver with no help. Also, if I hook up to an external monitor, the lines don't appear. Also, after just about 30 minutes of use or less, my laptop gets extremely hot, so much so that it's uncomfortable to hold on my lap. Now, if I leave it shut down for 2 hours or more, when I turn it back on, the lines will be gone. And they never appear spontaneously. If I left it on all the time, without closing the lid, they would never show up. what do you think?

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