Just following up in case it is of interest.
I did hear from one user of a 6xxx card with the latest firmware
running ok with NetBSD 1.6, so I went ahead and upgraded the firmware
on mine, and it is now happily initializing a mirror on my new disks:

twe0: 4 ports, Firmware FE6X 1.02.28.053, BIOS BE6X 1.07.02.005
twe0: Monitor ME6X 1.01.00.028, PCB Rev2    , Achip V4.40   , Pchip V5.70   
twe0: port 0: MAXTOR 6L080L4                           76345 MB
twe0: port 1: MAXTOR 6L080L4                           76345 MB
twe0: port 2: ST3300622A                               286168 MB
twe0: port 3: ST3300622A                               286168 MB
ld0 at twe0 unit 0: TwinStor, status: Normal
ld0: 76344 MB, 9732 cyl, 255 head, 63 sec, 512 bytes/sect x 156353536 sectors
ld1 at twe0 unit 2: TwinStor, status: Initializing
ld1: 279 GB, 36481 cyl, 255 head, 63 sec, 512 bytes/sect x 586070320 sectors

--sjg

On Mon, 21 Aug 2006 14:28:19 -0700, "Simon J. Gerraty" writes:
>
>If you have a 3w-6xxx raid controller with the latest firmware (see
>below), working with NetBSD I'd like to know.
>
>Alternatively if you have an earlier version of firmware on such a
>card working with big disks I'd like to know.
>
>I have a 3w-6410 raid controller, to which I want to add a pair of
>300G disks.