An essay in trauma.
An essay in trauma; this now easily is the worst, most badly damaged board I have ever seen . . . bar none.
This board has no business being in the repairs section other than I have no place else to put it for now; I see a hall of shame forthcoming though.
I have no words to fully describe the absolute trauma done to this board.
I do try in the following article, but the pictures really tell the story, all I
can do is narrate.
|Attached, the figurine of a monkey in Persian robes, playing the
cymbals. This item, discovered in the vault of the theatre, still
in working order; shown here. . . . oh wait, wrong narration . . .
Oh here we go:
How on earth can so much damage be
done to one
PCB! I've never in my life seen a board so badly damaged!
Warning: The following pictures show graphic damage to an Xbox PCB
and should not be viewed by people with stomachs too weak for such
things. . . Oh and the pics are kind of large as well.
|In this first photo I've highlighted three things across
five zones. First we'll cover the most fatal part: The
yellow portion. This highlights a trace torn back nearly under the
MCPx. Even on a good day I'm not sure I could fix this. The
area in red near the MCPx should show why: There is so much
general trauma to the solder mask that any attempt at soldering would be
nearly guaranteed to cause a bridge. While I could throw this
under the microscope and try to deposit a new trace and weld it to the
old one, I think that would still be marginal at best. The other
red highlight illustrates some general damage to D0. While I have
not even tried to check continuity to the TSOP, based on a close
examination, I'd bet that the connection is toast. Finally on to
the two portions highlighted in cyan. In both these cases both
pads for the components have been physically torn from the board.
It's hard to tell if the pads were heated until the epoxy fell apart or
if the damage was purely mechanical aside from heat. My best guess
is that R7D3 is heat related failure while C7D3 was predominately
physical (non-heat) damage.
|This is just a closer shot of D0 so you can see what I'm
talking about in the above section as in that shot D0 was outside the
plane of focus.
|Hopefully this pic is obvious as to what I'm showing.
How do you damage something so robust as a eyelet for mechanical
retention? (Photo scaled to 50%)
|While not impressive, this shot shows trouble waiting to
happen. Note all the detritus on the PCB (MCPx is in the photo on
the right). All this buildup is on relatively critical signals
(based on proximity to the MCPx) and under the right conditions can be
at least partially conductive. This low level conductivity can
cause erratic behavior which would be quite difficult to troubleshoot.
|Here we have a view of a cap near the memory that has
clearly been through some sort of re-work. Not sure if I would
trust it anymore based on previous slides :-) (inset photo is just
another view of the same component)
|UPDATE 13OCT2004 0920:
Hmmmm. I seem to have missed a missing component;
not that it would be too hard to do on a board this bad. The other
memory pads on the topside of the board (where one would solder
additional memory), is also missing the larger of the bypass caps.
In this case I bet that wouldn't matter as the memory is not installed
anyway. I wonder if there is anything else I might have missed?
|no pic available ::sry::
|Now we flip the board over. . . . Hmmm surprisingly
little damage. In the Cyan highlight we have a little solder
splash that currently would not cause problems, but were it to shift
when bounced around in a box being carried to a LAN party, could have
disastrous results. In the Yellow highlight we have a component
with one pad torn away, this would be fixable with a little effort.
Finally in the red highlight we have a component where the solder is
still there but the component is not. This is indicative of rough
handling and the component leadframe was not as strong as the PCB pads
or solder joint.
UPDATE 14OCT2004 0824:
The portion in yellow
is from a botched TSOP flash. Normally there is no component on
these pads. They are bridged as part of enabling write access to
the TSOP. Well now, that still doesn't mean it's not fixable, in
fact it's even easier to fix compared to if there was a component
missing. (if you wanted to fix it at all). Thanks to
A@ron and lordvader129 at Xbox-scene for pointing out my brain fart :o
|While I can often fix anything handed to me this one is
an exception. I knew, even before it arrived, that I was going to
have a good time laughing when I saw it. There is so much damage I
may just try to fix it to see if it is even possible . . . if I ever
have a spare couple of hours.
So in keeping with my new tradition, the
key takeaways from this are:
- If you're like the guy who did this: Drop the soldering iron and
step away (may want to unplug it first though)
- If you see a trace starting to lift up from the PCB . . . STOP
and send the board to someone who can fix such things. That
you got in the predicament of the trace lifting is good enough to
make it highly unlikely you can fix it.
- If you blow a component off the board, no big deal, just replace
it. If, on the other hand, you blow away the pads for said
component, then the same rules apply as for a lifted trace.
- If you can top this for damage to a board send it to me and I'll
do a write-up on it too. :-)