hello

> First of all, no pdp-11 compatibility. :-)

this is true!

> But actually, what I miss are a real front end! Heck, ^P shouldn't halt
> the system, it should just throw you back to the FE. That's not something
> that has anything to do with the VAX. And you should be able to check the
> temp at various places in the cab, and also the quality of the regulated
> powers, and all in software. And it should be *big*. The 6000-series are
> small machines. You can't take machines that size seriously.

small? well, if it fits in one cabinet, i guess you can call it small. 
a 6260 is pretty power-hungry, though, and is still bigger than a 
refrigerator. 

and i thought my 11/750's were marginally large.. :-) 
well, i fyou have the real estate and the electricity, an 8650 is a very 
groovy machine. i barely have room for my 6000 or my 750s!!! 

> > the 86x0's are the last of the 780-like machines, that is true.. 
> 
> Yup.
> Or 11/79x, as they are also known...

yeah.. this is a definite plus in my book, despite the architectural 
purity of some other VAXen, those which are still bit-for-bit-comatible 
withthe 780 have a sepcial status. However, the nexus model in the 6000s 
is very very attractive to me. This is one of the true beauties of the 
VAX architecture, and one of th eplaces where its superiority shines 
bright, in the concept itn he virtual memory system of a nexus and the
means of communication therewith- paged scatter gather virtual-addressed 
DMA. nothing else. the whole machine talks that way. it takes davantage 
of an architecture in ways that nothing else can come close to. 
now, the use of the nexus mechanism in something liek an 86x0 is still 
spiffy, and it _does_ have all those nexus slots, but th eonly thing that 
exists to plug into them is unibu and massbus adapters, perhaps a CI 
adapter. 

> I'm not that sold into ethernet cards that manipulate page tables. :-)

hey! thats the purest VAXish way of doing it! its the Virtual Address 
eXtension, remember!!! memory is central to it all! virtual memory! 

> I am, however, sold on separate busses for everything. Massive bandwidth!

true, but an XMI is damn fast, too. the XMI is more to be likened to the 
nexus interconnect in the 86x0 than to a unibus or massbus. 
and you can stick in multiple processors, since after all theyre just 
another device on the bus. 

> Two A-buses, SBI, many unibuses, many massbuses, separate memory bus. Can
> you not dig it?

oh, i can dig it!! 

> 
> Distributed power, man. XMI may be nifty and all, but once you really load
> an 86x0 up, it will burn cycles.

:-)
well, nobody can beat a VAX for BTU's per instruction!!


> Since I've never had the pleasure to work with anything larger than the
> 8650, I'll take your word for it then, change my remark to just the
> 9000...

yeah, theyre nothing like the 86x0s. the 7000 and 10000 are identical to 
the DEC7000 and DEC10000 AXP systems, expcept for an NVAX5 processor 
instead of a 21064. not very vaxlike machines. the 9000 i dont know much 
about. theyre very odd machines, and extremely rare. One is goign on sale 
at ebay right now, though. only like 500 of them were ever made. Theyre 
evidently damn cool though. 

> I have access to two 8650... :-)

very cool! if only i had a big house, i'd be asking how i coudl get my 
hand son one :) 

> 
> ...*what*??? An 8650 is a small cabinet??? What on earth for? Are you for
> placing your brain is a glass jar too? :-)


hey!!! i appreciate huge computers, and i can REALLY dig a row of 
cabinets in the form of an 8650 whirring away chowing down on bits from 
around the world day and night. however, i live in a small house in an 
area where elctricity is expensive!!! 

> 
> It's the whole package that makes it so attractive!
> 
> Imagine this:
> 
> A dark room, an 8650 and a terminal.
> The 8650 has the doors opened. Turning the power on on the 8650 just turns
> on a single diode on one power supply in the 8650. The terminal shows that
> the front end is booting. After a while the terminal prints:
> "INITIALIZING POWER"
> and one after one, the power supply LEDs lights up, and after about 8
> seconds, you have a nice warm glow from a line of power supplies, all now
> initialized and supplying power.
> "INITIALIZING CPU"
> and you know that the CPU is now fed microcode from the RL02 on which the
> front end is running. You also know that if you care to, you can get to
> the RT-11 prompt on the front end, start up your favourite editor and
> change the microcode you you like that. Once this step is done, you'll
> actually have a VAX. Before this, there is nothing.
> ("And the FE loaded the microcode and said ''Let there be VAX'', and there
> was VAX, and everyone was happy.")
> "INITIALIZING MEMORY"
> now the memory system gets fed whatever it likes. Soon the system will
> actually be a whole computer, who will start to boot, or whatever,
> depending on how you set the keys.
> 
> Ahhh, drool. Now, that's a computer.

*grin*

> 
> "6000s? We don't need to stinkin' 6000s!" :-)


hrrrmmmm


envious,
isildur