And out of GS.cpp, this is the error condition. Attempts to access the memory around where it thinks the ring buffer starts, completely fail.
if( g_pGSRingPos != GS_RINGBUFFERBASE ) {
SysMessage("Cannot alloc GS ring buffer\n");
exit(0);
}
SysMessage("Cannot alloc GS ring buffer\n");
exit(0);
}