Re: Larger memory option for VAXstations

[emanuel stiebler <emu%e-bbes.com@localhost>]

On 2015-08-19 04:50, Johnny Billquist wrote:
> On 2015-08-18 22:06, John Klos wrote:
> > Hi,
> > 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?

Cheers