Theres no differecne between the DECsystems 5x00 for x=4,8,9, etc and a 
microVAX 3[469]00. Theyre basically mayfair machines with MIPS processors 
instead of VAX processors. They usually are found in standard BA213 boxen 
which are also often found mounted in racks. Theyre much more like a VAX 
than a DECstation, aside from the processor. All you have to do to make a  
uVAX 3n00 out of one is change the processor board. I recently donated a 
5400 to the NetBSD/pmax development effort since they lacked such a 
machine to do any testing on. The work theyve done there should be useful 
in a lot of ways for supprting uvax 3x00s, but i think theres a lot of 
overlap as it is. All the MIPS cpu support and VM stuff is based on Mach, 
though, which is absolutely disgusting. Most of it's been reqritten (T. 
Nishimura a couple months ago totally revamped virtual emory on the 
dECstations) but it does still carry some machness with it. (still, use 
it, its good stuff!) personally, i prefer Ultrix though, when it really 
comes down to it.. :-)

On Sun, 5 Sep 1999, Simon Burge wrote:

> David Brownlee wrote:
> 
> > 	Definitely interested in some of the kit :)
> > 	Could I ask where you are located, and if the DECsystem 5400 is
> > 	a Qbus based MIPS box?
> 
> Yes it is.  The pmax models page doesn't have much on this, but I'm digging now.
> One quote:
> 
> 	These are all systems based on the qbus, so you have to know:
> 	the small label on the front of the enclosure doesn't says
> 	what's in there: ... DECsystem 5400's can be converted to
> 	MicroVAX 3500's
> 
> Simon.
>