> 	
> emanuel stiebler wrote:
> 
	>So, as I see it (could be wrong) but the cpu boards of ka675,
ka680,
	>ka690 are the same, 
	>but only different speed grades (aka l4002-aa, l4002-ab, l4002-ac)
	>They look pretty much simililar, there is only one different
oscillator.

	You're right - everything beyond the VAX 4000-300 is NVAX.
	The boards are largely similar and the only differences should
	be the occasional crystal and a few parts at different speeds.

	The VAX 4000-300 was a Mariah-based CPU (KA670). It used
	the MS670 memory modules (L4001). 

	The later NVAX systems used the MS690 modules and a
	slightly revised backplane. The later VAX 4000-300 systems
	also had that same backplane. The part number is 54-19354-01,
	which you appear to have. (In fact, since your VAX 4000-400
	works, you already have the necessary backplane and memory).

	>about memory: What I have here are two l4004-cp boards, which are
	>64MByte each.
	>My guess is, that this is the ms690 memory.

	I believe that it is (since MS670 is L4001) but I don't
	have a parts list to check against right now.

	>And, the cpu stays in "F" on the LED, it looks it even doesn't try
to
	>test the memory.
	>(if I remove the memory out of the 4000/400 system, I get at least
the
	>message, that there is no memory)

	This is not good news. If all you've swapped is the CPU
	module, then you quite possibly have a dead CPU module.

	The PSU should have a few indicators (AC OK, DC OK,
	Over temp & Fan fail); I assume none of these are
	lit.

	An F on the hex display is usually quite bad: either the
	CPU is dead or the PSU is dead. Since it works with the
	VAX 4000-400 CPU and not with the VAX 4000-600 CPU
	it would suggest that the 600 CPU is dead (since the
	PSU is obviously alive).

	Antonio