Q: Lines of Red Hash on Monitor
I have a PowerPC G5 desktop Mac running OSX 10.5.8 (cannot go to a higher system). My monitor is an HP 2335 (23"). Both are clearly quite old at this point.
I am now experiencing a periodic display of Red Hash Marks on the screen. It might start in one window, and then progress to other windows and the desktop. The original image remains, but these red marks appear on top. The marks look like lines of very tiny text stringing horizontally across the window. The size of the marks is equivalent to about a font size 2 or 3. The marks are not letters, but are all vertical lines. They appear text in that there are horizontal groups of many lines, and then several spaces, and then more lines. The pattern is not regular.
If I move a window that has the marks, the marks move with the window. Sometimes if I move the window partially off the screen boundary, and then back, the hash marks are "erased" from the portion that was off the screen. Sometimes the marks aren't erased.
If I click around and move different windows, the marks eventually disappear.
I suspect I'm having a monitor or video board problem. Any thoughts or solutions?
Mike
Mac OS X (10.5.8)
Posted on Sep 25, 2013 9:53 AM