Created attachment 118448 [details]
apitrace of hang

Not exactly sure how useful it is, but I have attached an excerpt of an
apitrace of the unigine valley demo. I had to cut out most of it, due to the
size of it - I've run it several times, and the size has always been >500MB.
The last thing in the trace was always glXSwapBuffers, so the excerpt consists
of the contents between the last and the next to last glXSwapBuffers lines.