> Now can _anyone_ suggest some frobbing that NetBSD is doing that might
> cause this? 
> 
> It is running the same kernel it has been for weeks without any sign
> of trouble.  It is 95-08-18 vintage, I'm running the same sources on
> zen which has been up and happy since that date.

I should have pointed out that the system is using pccons and on both
occasions the screen ``burning'' happened while at the shell prompt
just after booting - and even before it finnished booting.  So what
every is causing it is probably happening during device probing.

There are not many devices configured - config below.

#	$Was: GENERIC,v 1.15 1995/04/17 22:44:38 brezak Exp $
#
#	NOT -- NoteBook config
#

machine		i386		# architecture, used by config; REQUIRED

makeoptions	CC="cc -Werror"

#options		I386_CPU	# CPU classes; at least one is REQUIRED
options		I486_CPU
#options		I586_CPU
#options		MATH_EMULATE	# floating point emulation

###options	DUMMY_NOPS	# speed hack; recommanded
options		XSERVER,UCONSOLE
options		MACHINE_NONCONTIG

maxusers	64		# estimated number of users
options		TIMEZONE=0	# time zone to adjust RTC time by
options		DST=0		# daylight savings time used by RTC

options		INSECURE	# allow memory access

# <sjg>s options
options		CHILD_MAX=256		# sets MAXUPROC
options		NO_LINKDIR_INO		# no stupid symlink behaviour
#options		IP_NO_SRCROUTE		# no LSRR or SSRR
#options		IP_IFADDR_ONLY		# only accept IP packets to correct address
#options		LP_SIMPLE_PROBE		# always find printers :-)
# back to generic

options		SWAPPAGER	# paging; REQUIRED
options		VNODEPAGER	# mmap() of files
options		DEVPAGER	# mmap() of devices

#options		DDB		# in-kernel debugger
#makeoptions	DEBUG="-g"	# compile full symbol table
#options		DIAGNOSTIC	# internally consistency checks
options		KTRACE		# system call tracing, a la ktrace(1)

options		SYSVMSG		# System V-like message queues
options		SYSVSEM		# System V-like semaphores
options		SYSVSHM		# System V-like memory sharing
###options	SHMMAXPGS=1024	# 1024 pages is the default

options		COMPAT_NOMID	# compatibility with 386BSD, BSDI, NetBSD 0.8,
options		COMPAT_09	# NetBSD 0.9,
options		COMPAT_10	# NetBSD 1.0,
options		COMPAT_43	# and 4.3BSD
options		TCP_COMPAT_42	# TCP bug compatibility with 4.2BSD

options		COMPAT_SVR4	# binary compatibility with SVR4
options		COMPAT_IBCS2	# binary compatibility with SCO and ISC
options		COMPAT_LINUX	# binary compatibility with Linux

options		USER_LDT	# user-settable LDT; used by WINE
options		LKM		# loadable kernel modules

options		FFS,QUOTA	# UFS and quotas
#options		LFS		# log-structured file system
options		MFS		# memory file system

options		NFSCLIENT	# Network File System client
options		NFSSERVER	# Network File System server

#options		CD9660		# ISO 9660 + Rock Ridge file system
options		MSDOSFS		# MS-DOS file system
#options		FDESC		# /dev/fd
options		FIFO		# FIFOs; RECOMMENDED
options		KERNFS		# /kern
options		NULLFS		# loopback file system
#options		PORTAL		# ?
options		PROCFS		# /proc
#options		UMAPFS		# NULLFS + uid and gid remapping
#options		UNION		# union file system

###options	GATEWAY		# packet forwarding
options		INET		# IP + ICMP + TCP + UDP
#options		NS		# XNS
#options		ISO,TPIP	# OSI
#options		EON		# OSI tunneling over IP
#options		CCITT,LLC,HDLC	# X.25

config		netbsd	swap generic
options		GENERIC

isa0	at root
pci0	at root

#options	PCMCIA_DEBUG
pcic0   at isa? port 0x3E0 flags 0
pcmciabus0 at isa? iomem 0xd4000 iosiz 4096

#ed0     at pcmciabus? port 0x300 	irq 10
ep0     at pcmciabus? port 0x300 	irq 5

npx0	at isa? port 0xf0 irq 13	# math coprocessor

pc0	at isa? port 0x60 irq 1		# generic PC console device
###vt0	at isa? port 0x60 irq 1

com0	at isa? port 0x3f8 irq 4	# standard PC serial ports
#com1	at isa? port 0x2f8 irq 3
#com2	at isa? port 0x3e8 irq 5
###com3	at isa? port 0x2e8 irq 9
###ast0	at isa? port 0x1a0 irq 5	# AST 4-port serial cards
###com*	at ast? slave ? flags 1
###boca0	at isa? port 0x100 irq 5	# BOCA 8-port serial cards
###com*	at boca? slave ?
###rtfps0	at isa? port 0x1230 irq 10	# RT 4-port serial cards
###com*	at rtfps? slave ?

###cy0	at isa? ...

#lpt0	at isa? port 0x378 irq 7	# standard PC parallel ports
lpt0	at isa? port 0x378	# standard PC parallel ports
#lpt1	at isa? port 0x278
#lpt2	at isa? port 0x3bc

#lms0	at isa? port 0x23c irq 5	# Logitech bus mouse
#lms1	at isa? port 0x238 irq 5
#mms0	at isa? port 0x23c irq 5	# Microsoft InPort mouse
#mms1	at isa? port 0x238 irq 5
pms0	at isa? port 0x60 irq 12	# PS/2 auxiliary port mouse

#aha0	at isa? port 0x330 irq ? drq ?	# Adaptec 154[02] SCSI controllers
#aha1	at isa? port 0x334 irq ? drq ?	# Adaptec 154[02] SCSI controllers
#scsibus* at aha?
#ahb0	at isa? port ? irq ?		# Adaptec 174[024] SCSI controllers
#scsibus* at ahb?
#aic0	at isa? port 0x340 irq 12	# Adaptec 152[02] SCSI controllers
#scsibus* at aic?
#bt0	at isa? port 0x330 irq ? drq ?	# BusLogic [57]4X SCSI controllers
#bt1	at isa? port 0x334 irq ? drq ?	# BusLogic [57]4X SCSI controllers
#bt2	at isa? port ? irq ?
#scsibus* at bt?
#ncr*	at pci? bus ? dev ?		# NCR 538XX SCSI controllers
#scsibus* at ncr?
#sea0	at isa? iomem 0xc8000 irq 5
#scsibus* at sea?
#uha0	at isa? port 0x330 irq ? drq ?	# UltraStor [13]4f SCSI controllers
#uha1	at isa? port 0x334 irq ? drq ?	# UltraStor [13]4f SCSI controllers
#uha2	at isa? port ? irq ?		# UltraStor 24f SCSI controllers
#scsibus* at uha?
#sd*	at scsibus? target ? lun ?	# SCSI disk drives
#st*	at scsibus? target ? lun ?	# SCSI tape drives
#cd*	at scsibus? target ? lun ?	# SCSI CD-ROM drives
#ch*	at scsibus? target ? lun ?	# SCSI autochangers

fdc0	at isa? port 0x3f0 irq 6 drq 2	# standard PC floppy controllers
###fdc1	at isa? port 0x370 irq ? drq ?
fd*	at fdc? drive ?

#mcd0	at isa? port 0x300 irq 10	# Mitsumi CD-ROM drives

wdc0	at isa? port 0x1f0 irq 14	# ST506, ESDI, and IDE controllers
###wdc1	at isa? port 0x170 irq ?
wd*	at wdc? drive ?

#wt0	at isa? port 0x300 irq 5 drq 1	# Archive and Wangtek QIC tape drives

#ed0	at isa? port 0x280 iomem 0xd0000 irq 9	# WD/SMC, 3C503, and NE[12]000
#ed1	at isa? port 0x250 iomem 0xd8000 irq 9	#   ethernet cards
#ed2	at isa? port 0x300 iomem 0xcc000 irq 10
###eg0	at isa? ...				# 3C505 ethernet cards
###el0	at isa? port 0x300 irq 9		# 3C501 ethernet cards
#ep0	at isa? port ? irq ?			# 3C509 ethernet cards
#ie0	at isa? port 0x360 iomem 0xd0000 irq 7	# StarLAN & 3C507 ethernet cards
###le0	at isa? port 0x320 irq 10 drq 7		# IsoLan, NE2100, and DEPCA
###de*	at pci? bus ? dev ?

#pss0	at isa? port 0x220 irq 7 drq 6  # Personal Sound System
#sp0	at pss0 port 0x530 irq 10 drq 0	# 	sound port driver

#sb0	at isa? port 0x220 irq 7 drq 1	# SoundBlaster
wss0	at isa? port 0x530 irq 10 drq 0	# Windows Sound System
#pas0	at isa? port 0x220 irq 7 drq 1	# ProAudio Spectrum
###spkr0	at isa? ...

pseudo-device	loop	1		# network loopback
pseudo-device	bpfilter 8		# packet filter
pseudo-device	sl	2		# CSLIP
pseudo-device	ppp	2		# PPP
pseudo-device	tun	2		# network tunneling over tty

pseudo-device	pty	64		# pseudo-terminals
#pseudo-device	tb	1		# tablet line discipline
pseudo-device	vnd	4		# paging to files