>Could it be, that the only difference between the VAX 4000/400 and
the 4000/500
	>is the CPU chip? (KA675 uses Mariah, KA680 uses NVAX). Would be not
that bad,

	That's bad enough: AFAIK both the KA675 and the KA680 are NVAX
based.
	(And so are the KA692 & KA694). 

	Depending on heatsinks etc. - no, don't knock them off just to check
:-) -
	both boards should have a DC246 (the NVAX chip). 

	The KA675 runs the NVAX at 16ns, the KA680 at 14ns.
	Both have a backup cache of 128KB. The KA675 disables the
	NVAX on-chip VIC (but I'm fairly sure the other on-chip cache
	is left enabled).


	> so i have a physical machine here to do the 675 port and the 680
should work
	> nearly "automagically". (Yes, the donator of the TM is waiting for
a kernel :)

	Which tech manual are you looking at? I've just looked at the
KA675/KA680/KA690
	maintenance guide and it agrees with my recollection. I don't think
any VAX 4000
	used a Mariah: The 100-, 400, 500- & > 500 all used NVAX. The
4000-300 was
	Rigel (IIRC), the 4000-200 was CVAX.

	One of the uVAX 3100 series used a mariah ( uV 3100-80 ??) and the
VS4000-60
	also used a Mariah. The only other one that springs to mind is the
6000-500 (for which
	the chipset was designed).

	>Does anybody know about these 2 boards? (And does anybody have a
hot hint for
	>some strange problems looking to me like a bit more complicated
interrupt
	>handling than on VAXstations and earlier VAXen, especially KA670).

	I still have access to various VAX 4000-5/6/700 systems and there
used
	to be a VAX 4000-400 CPU card kicking around (although I don't
expect 
	I'll manage to find that!)

	I don't think there is much you need to do differently to support
	the KA675 if you already support the KA680 (except leave the VIC
	off obviously - I believe the console turns it off somewhat
	abruptly, possibly patching the NVAX ucode on the fly to
	do so).

	I have no idea about interrupt problems.
	 
	>Ok, i have lots of boards to scan for the visual field guide the
weekend. I
	>think the DIV32 pictures could be interesting, this card doesn't
seem to be
	>very common...

	Dunno - I had (possibly still have) two of those but I only ever
	saw one DEQRA and one LNV21. I never actually saw anyone use
	any of these though!

	Antonio
	arcarlini@iee.org