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Re: Larger memory option for VAXstations

On 2015-08-19 04:50, Johnny Billquist wrote:
On 2015-08-18 22:06, John Klos wrote:
Faster SCSI wouldn't be so bad, too :)

But you like to keep all your old drives too, right?
So not knowing, what nemonix really did, they probably just plugged in a second SCSI controller into the system with something like 53c875,
and wrote additional drivers to access it ...

I don't have any hardware information, but an educated guess would be
that you need some additional address lines routed from the CPU to the
memory sockets.

Anybody knows, if they are there?

But from a CPU point of view, there is nothing speical about
going to 512 Megs. Or even more. But if you go for more physical memory,
you need an NVAX (which I think the 4000 machines have), and the OS
needs to change the mode of the CPU, which I suspect VMS will not do on
a 4000 machine, as they would not expect you to have that amount of
physical memory that would require changing from the default mode.

The firmware tells the OS, how much memory you have, right?

Of course, we could do that in NetBSD, but I don't think we support a
single NVAX type machine yet...

4000/90 and up are supported, aren't they?


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