> At least I tried several other PCI video cards instead of the pbxgb
> powerstorm card, but with none of those I got any video output :-(

My 255/PowerStrom works just fine (ws,1.4K)

NetBSD 1.4K (OPIUM) #0: Sat Oct  9 18:04:22 EST 1999
    profroot@opium.iq.org:/share/netbsd/usr/src/sys/arch/alpha/compile/MONOAMINE
AlphaStation 255/233, 232MHz
8192 byte page size, 1 processor.
total memory = 32768 KB
(2000 KB reserved for PROM, 30768 KB used by NetBSD)
avail memory = 20752 KB
using 769 buffers containing 6152 KB of memory
mainbus0 (root)
cpu0 at mainbus0: ID 0 (primary), 21064A-2 (pass 1.1)
apecs0 at mainbus0: DECchip 21072 Core Logic chipset
apecs0: DC21071-CA pass 2, 128-bit memory bus
apecs0: DC21071-DA pass 2
pci0 at apecs0 bus 0
pci0: i/o enabled, memory enabled
ncr0 at pci0 dev 6 function 0: ncr 53c810a fast10 scsi
ncr0: interrupting at isa irq 11
ncr0: minsync=25, maxsync=206, maxoffs=8, 16 dwords burst, normal dma fifo
ncr0: single-ended, open drain IRQ driver
ncr0: restart (scsi reset).
scsibus0 at ncr0: 8 targets, 8 luns per target
sio0 at pci0 dev 7 function 0: Intel 82378ZB System I/O (SIO) (rev. 0x43)
vga0 at pci0 dev 13 function 0: Digital Equipment TGA2 (rev. 0x22)
wsdisplay0 at vga0
de0 at pci0 dev 14 function 0
de0: interrupting at isa irq 10
de0: DEC 21040 [10Mb/s] pass 2.4
de0: address 00:00:f8:21:b3:2c
de0: supplying EUI64: 00:00:f8:ff:fe:21:b3:2c
isa0 at sio0
com0 at isa0 port 0x3f8-0x3ff irq 4: ns16550a, working fifo
com0: console
com1 at isa0 port 0x2f8-0x2ff irq 3: ns16550a, working fifo
lpt0 at isa0 port 0x3bc-0x3bf irq 7
wss0 at isa0 port 0x530-0x537 irq 9 drq 0: CS4231 or AD1845
audio0 at wss0: half duplex
pckbc0 at isa0 port 0x60-0x64
pcppi0 at isa0 port 0x61
spkr0 at pcppi0
isabeep0 at pcppi0
fdc0 at isa0 port 0x3f0-0x3f7 irq 6 drq 2
mcclock0 at isa0 port 0x70-0x71: mc146818 or compatible
scsibus0: waiting 2 seconds for devices to settle...
sd0 at scsibus0 targ 0 lun 0: <DEC, RZ26F    (C) DEC, 1Q04> SCSI2 0/direct fixed
sd0(ncr0:0:0): 10.0 MB/s (100 ns, offset 8)
sd0: 1001 MB, 3117 cyl, 8 head, 82 sec, 512 bytes/sect x 2050860 sectors
de0: enabling 10baseT port
sd1 at scsibus0 targ 3 lun 0: <MAXTOR, LXT-213S, 4.20> SCSI1 0/direct fixed
sd1: 202 MB, 1310 cyl, 7 head, 45 sec, 512 bytes/sect x 415436 sectors
IPsec: Initialized Security Association Processing.
root on sd0a dumps on sd0b
root file system type: ffs
de0: starting DAD for fe80:0001::0200:f8ff:fe21:b32c
de0: DAD complete for fe80:0001::0200:f8ff:fe21:b32c - no duplicates found
wsdisplay0: screen 0 added (80x25, vt100 emulation)
wsdisplay0: screen 1 added (80x25, vt100 emulation)
wsdisplay0: screen 2 added (80x25, vt100 emulation)
wsdisplay0: screen 3 added (80x25, vt100 emulation)
wsdisplay0: screen 4 added (80x25, vt100 emulation)