The strange black circle of dead pixels you see is physical damage to the display, you should get the display replaced.
It will have been caused by either water damage, a latent manufacturing defect, flexing, or excess force. It certainly cannot be caused by software or leaving an image on screen for too long. It can be avoided by ensuring the laptops are cared for by each child; child ownership. Depending on how it is caused, the damage may spread to nearby pixels. I would not deploy this to a child, it would be frustrating for them, and it may get worse without a teacher noticing. -- James Cameron http://quozl.linux.org.au/ _______________________________________________ IAEP -- It's An Education Project (not a laptop project!) IAEP@lists.sugarlabs.org http://lists.sugarlabs.org/listinfo/iaep