> > The problem is something with the LANCE addressing of memory.  The
> > LANCE chip can only address 16MB of memory, and by some unknown
> > reason it works good when there are less than 16MB in the machine.
> 
> This sounds suspicious.  16M is 22 bits.  Aren't Q-bus addresses 22
> bits wide?  Perhaps the lance driver is setting up the qbus mapping
> registers wrong or something, such that the physical address of the DMA
> buffer is mistakenly getting used as the Q-bus address of the buffer?
> Something like that could cause this sort of symptom.
> 
Please recalculate that. First; 16M is 24 bits :-) Second; VAXstations
doesn't have any bus at all so the Qbus characteristics is irrelevant.
A VAXstation do DMA into physical memory without any mapping registers
at all.

-- Ragge