(In reply to iive from comment #57)

I believe I've already tried with nodma under Xonotic, as I previously
attempted playing with the following options and still got the crash:

export
R600_DEBUG=3Dcheckir,precompile,nooptvariant,nodpbb,nodfsm,nodma,nowc,noout=
oforder,nohyperz,norbplus,no2d,notiling,nodcc,nodccclear,nodccfb,nodccmsaa

I've also checked out the BIOS, no overclocking settings are responsible. T=
he
freeze happened even with the failsafe defaults of my BIOS in use.

And during the netconsole test, I did enable and use the SysRq keys (RESUB)=
...
nothing got printed to the other machine. SysRq doesn't seen to do anything
after the freeze: Nothing happens if I press them, including the HDD led wh=
ich
never flashes again indicating that even the drive is never used any more.

Loading a second kernel into memory sounds complicated and much more danger=
ous.
At this stage I also doubt even that would work, as the machine literally a=
cts
as if the whole system (CPU / RAM) is bricked and jammed upon crashing.