Help needed with 'panic: swtch'

[Roger Southwick]

[No matter where you go.......... there you are.  Buckaroo Banzai]

Greetings!

    About 3 or 4 weeks ago, our hardware support folks swapped
out our CPU board set from our Vax 11/780 in an attempt to isolate a 
problem in which the system would crash with a 'CPU DOUBLE ERROR FAULT'
In the meantime, we have their board set.  

Well, this fixed the double error problems, but now we are being 
plagued with 'panic: swtch' crashes!  

We have looked into the crash dumps, and found only that, yes indeed,
the system should have paniced (in one case the process table got
munged!).

The problem seems to occur at random times of the day, and at
random intervals apart (right now we've been running over a week
with no crashes, other times the system crashes every other day).

We are running 4.3BSD on the system which is configured as
follows:

    Main cabinet:
	Vax 11/780, FPA, 12 Meg of DEC and Trend Data Memory with
	an E type memory controller.

    MBA # 0
	RP07
    
    MBA # 1
	TU78,
	RM03 (tiny!)
	
    UBA # 0
	3 Able VMZ-32's,
	1 DEC DZ11 (unused),
	DEC TS11 hooked to a TU80 (for users),
	Interlan NI-1010 Ethernet card
	Network Systems PI-13 Hyperchannel card
    
    UBA # 1
	2 Able VMX-32N's,
	DEC UDA50
	    DEC RA81


Any ideas, suggestions or free dynamite would be greatly appreciated.
The users have already voted to change the name of the machine from
'dadla' to be 'deadla'.

Please respond via E-mail, not by posting...  if there's enough
interest via the mail, I'll post a summary.

		-Roger (rogers at dadla.tek.com)

BELLnet (phone):	(503)-629-1911

SNAILnet (U.S. Mail):	Roger Southwick
			Tektronix, Inc.
			P.O. Box 4600, D.S. 92-731
			Beaverton, Oregon 97075