Bug#229072: Probably pilot error, but see #229628
I now suspect that this problem is simply due to the chipset not being
supported in this version of the X server. My comments about the
server working, but then locking up, were probably in reference to an
experimental version (4.3.0) of the X server that I'd installed (and
then forgotten about!) precisely because it was the only version I
could find that *did* support my chipset.
Bug 229628 contains details about the experimental version locking up.
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