Just in time for the holidays, my computer (monitor) has decided to light-up with green holiday blinkers. They appear at log-in (prior to logging in) on the desktop and within programs. Spent some time with tech support and the only time they didn't show up was in Safe Mode and Screen Share. We created a new account and they appeared as well. After several test (Option-Command-R-P, Shift at restart, and removing a plist file) the problem continued. They originally felt it was software (3rd party), but since the problem appears before logging-in, they suspect it may be hardware. The last thing we did was run some kind of capture test (dmgpart). They said they will analyze the data and get back to me. I noticed that most of the threads on this were dated. If anyone has any idea, feel free to provide. Fortunately, I have the extended warranty. As soon as I get a reply, I'll update this thread.