Hello

My new pair of hard disks was identical but now are different:
sd0 lost more of 2 GB!!!

ahc1 at pci0 dev 9 function 0
ahc1: interrupting at irq 11
ahc1: aic7880 Wide Channel A, SCSI Id=7, 16/255 SCBs
scsibus0 at ahc1: 16 targets, 8 luns per target
[...]
sd0 at scsibus0 target 5 lun 0: <IBM, DDYS-T36950N, S93E> SCSI3 0/direct fixed
sd0: 32768 MB, 15110 cyl, 12 head, 370 sec, 512 bytes/sect x 67108864 sectors
     ^^^^^                         ^^^                       ^^^^^^^^
sd0: sync (50.0ns offset 8), 16-bit (40.000MB/s) transfers, tagged queueing
sd1 at scsibus0 target 6 lun 0: <IBM, DDYS-T36950N, S96H> SCSI3 0/direct fixed
sd1: 35003 MB, 15110 cyl, 12 head, 395 sec, 512 bytes/sect x 71687340 sectors
     ^^^^^                         ^^^                       ^^^^^^^^
sd1: sync (50.0ns offset 8), 16-bit (40.000MB/s) transfers, tagged queueing

This was while I was trying to put 50%NetBSD-1.6/i386 and 50%winxp in
my PIII/256 MB RAM.  (My first experience in a lot of years).
My first attempt was "first NetBSD and then winxp". It didn't work because
I couldnt see more of 1024 cyls in sd0 with the install program.

My second attempt was "first winxp and then NetBSD". I installed fine winxp. Then
when I tried to install NetBSD, i saw the new reduced size of my hard disk. It
didn't like me and I stopped my installation in order to reformat (low level) the
hard disk with the utilities of my scsi controller. (Adaptec AHA-2940UW Pro scsi
bios v2.11.0 (c) 1998 Adaptec).  My plan was to rescue the original size.

After the low level format and verify, my disk keep the new reduced size.

Does somebody can help me or give me some hint?

Thanks in advance

Heron Gallegos

More info: (if you have time to read it)
* I AM SURE the disks was exactly identical because, one day before,
I installed 1.6 in both, (full disks for NetBSD) I copied the disklabel
of sd0 to sd1, and I tested both disks over some hours, i.e., root
in sd0, usr in sd1, var in sd0, tmp in sd1, two swap areas, /usr/pkgsrc
in sd0, /usr/src in sd1, etc.  (To copy a file of 1898 MB from sd0
to sd1 takes 112 sec...17 MB/s, if you are interested in this data)

* There is not a new version for the firmware of my Adaptec SCSI-III
controller in the Adaptec web site (The latest is version 2.11.0 like
the original of my card)

* The manual of IBM for this model of disk says this:
Label capacity (MB)	36.70 GB
Sectors per track	512 - 528
Number of heads		12
Number of disks		6
Total data bytes	36,703,918,080
Total logical data blocks	71,687,340(445DCACh)
----------------------------------------------
Buffer to/from media [Mbit/sec]	280 - 452 Mbps
Host to/from buffer (interface	80 (68/80 pin FAST 40 WIDE)
transfer rate) [Mbyte/sec]	160 (68/80 pin Ultra 160)
Data buffer size		4096 MB (512 KB used by firmware)
Number of buffer segments	7 x 512 KB or 14 x 256 KB or 28 x 128 KB
Rotational speed [RPM]		10000
Recording density [Kbpi]	300 (Average) 352 (Max)
Track density [TPI]		20,000 (Average)
Areal density [Mb/sq.in.]	6250 (Max)
Data zone			11
-----------------------------------------
4.3 Cylinder allocation
Data	Physical	Sectors/
Zone	Cylinders	Track
0	0-378		504
1	379 - 2069	476
2	2070 - 3416	462
3	3417 - 6788	420
4	6789 - 7493	406
5	7494 - 8863	392
6	8864 - 10167	378
7	10168 - 11195	364
8	11196 - 11999	352
9	12000 - 13714	336
10	13715 - 15109	308