Fatal Error $0911

[smarti@gwis2.circ.gwu.edu (J. Scott Martin)]

I have had 2  //GSs go bad with the same error, "Fatal Error $0911".  The
first one died a year ago and does not even attempt to boot up.  The
second one works some of the time (about %75) but acts a little flaky and
passes the self diag test (apple-option on start up) almost 90% of the
time, when it does fail the self diag test it fails on 09000000
specfically 09010001.

If anyone out there has the Apple Technical Repair manuals, or has more
information about a "Fatal Error $0911" please post a follow up message. 
I have checked both the Firmware reference (nothing in there about
diagnostic testing) and the Hardware reference (nothing in there either). 


I am fully prepared to resolder components as need, using the older //GS
as a test system.  I am assuming that the built in diagnostic test is
testing sub-systems of the mother board and I will, with help, at least be
able to look at a section that has failed (rather than the whole thing). 
Thanks for any help that you may be able to offer.

-Scott