> 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.

					der Mouse

			       mouse@rodents.montreal.qc.ca
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