Hmm, did help a little bit
it did freeze like 2 min. later than before this BIOS upgrade & I even got the gdm started up, but then dead again
The logs are slightly different too, there are mainly Head, not so many Channel warn msgs.
the Xorg log only had one relevant WW :
(II) Loading extension NV-CONTROL
(WW) NVIDIA(0): WAIT (0, 6, 0x8000, 0x00000db8, 0x00000db8, 0)
so in fact, we are where we've been ... can you please clarify what is meant under Xid 16 and Xid 8 ??
and the Head or Channel keywords?
(if it's not a public secret
P.S. I am wondering whether it could be a problem with shared IRQs