Common frame buffer problems on 19" monochrome Sparcstations

[Paul Eggert]

We have found a problem with 9 out of 10 frame buffers in our
Sparcstations with 19" monochrome displays.  Bad frame buffers sometimes
display 14 brighter-than-white vertical stripes that stretch in a
horizontal band all the way across the display.  The presence and height
of the stripes seems to depend entirely on the bit pattern in the frame
buffer; even screenblank(1) does not make them go away.  The stripes blink
on and off during normal activity on the screen, and are thus fairly
distracting.  We have reproduced the problem under both X and SunView.
Other Sun customers have also reported the problem, and Sun has reproduced
it, but Sun does not have a fix yet.  If you have a new 19" mono
Sparcstation, you should check whether it has this problem before your
90-day warranty runs out.  Here's one way to create a bit pattern on your
screen that reproduces the problem; the glitches in this case are fairly
small, but our larger examples are harder to reproduce.

1.  Start with a Sparcstation 1 with a 19" monochrome display running
SunOS 4.0.3c.

2.  Rename all of the . files in your home directory, so that they don't
interfere with the test.

	% cd
	% mkdir X
	% mv .??* X

3.  Create a file named ~/.sunview with the following two lines.

	cmdtool   -Wp 641 848 -Ws 511  52 sh
	shelltool -Wp 569 438 -Ws 570 427 sh

4.  Log out.  Log in.

5.  Type the shell command 'sunview'.  Wait for SunView to start up.

6.  Move the mouse cursor about two inches southeast, so that it enters
the shelltool.  Wait for the shelltool's border to darken.

7.  Do you see a series of 14 spots brighter than normal screen white,
running in a narrow horizontal band about an inch from the bottom of the
screen?  If so, your Sparcstation has the frame buffer problem.  Call Sun.

8.  Don't forget to rename your . files back.

	% cd
	% rm .sunview
	% cd X
	% mv .??* ..
	% cd
	% rmdir X
	% logout