I just replaced my Adaptec 2940 with an Adaptec AIC-7892A U160/m
and got some new (faster) drives.

What I did was:
moved slackware from hda to NEW sda (seagate 160MB/sec)
moved gentoo from OLD sda (80MB/sec) to NEW sdb (160MB/sec)
(by moved, I mean I copied OS to a new drive)
All that worked out. I can boot to either version just fine.

The end result that I want is this:
ID0 - sda - seagate 160MB/sec - slackware
ID1 - sdb - seagate 160MB/sec - gentoo
ID2 - sdc - fujitsu 80MB/sec - shared /home
ID3 - sdd - fujitsu 80MB/sec - backup of of shared home.
(ignoring IDE devices for now).

The problem comes in when I try connecting my 2 80MB/sec drives. I have tried:
A- Both at the same time (ID 2 & 3 and 8 & 9) - card detects drives about 1/8 times
B- One at a time (ID 2 & 8) - card detecs drive about 1/8 times
C- 1 or both drives on the 2nd 68-pin channel - some CRAZY termination error that I
do not get when they are hooked up to the 1st 68-pin connector.

The 80MB/sec drives work fine IF both the 160MB/sec drives are out of the picture.
The issue is only when all 4 (or 3) are connected simultainiesly. I did get gentoo
to boot 1 time with 1 of the 80MB/sec drives detected by the card. WOW - the errors
that got thrown out loading the scsi card drivers.... ended up "ctl-alt-del'ing".

I tried about 2 1/2 hours last night doing about every possible combination of card
settings and drive jumper settings I thought had a reasonable chance of working.

Models of drvies, if needed, are:
Seagate ST318406LW (160MB/sec)
Fujitsu MAG3182MP (80MB/sec)

Any adivce???? please ????
-tw

I couldn't dig up any info on the AIC-7892A, so I'm not familiar with it, but I think ID 8 is reserved for the controller itself and can't have a drive with that ID. Does this card have two SCSI connectors, one U2W (80mb/s) and one U160? Because you can't mix the two on the same bus, just wondering how its hooked up physically.
Do the U2W drives have a jumper for termpower?

randyding
THANKS for the reply - I'm about at my wits end with this problem!!

ID 7 is for the controller

Good question - well, yes, it does have 2 68-pin internal connecters ( and 1 external which
will be used for my scanner, which is currently not connected.) But if 1 is for the 80's and 1 is
for the 160's, I'm not for sure. I bought the card locally used - so no docs. All I know is the chip
set (via lspci & looking at the card). I will work on getting the AHA-xxxx instead of the AIC-xxxx.

SIDE NOTE: in the scsi bios, it allows me to change the speed on all the ID's from 160 (default),
all the way down to I think it is 20, or something really low like that. So I set ID0 & ID1 at 160, and ID2 & ID3 at 80.

So no matter what I can't have all 4 drives on the same 68-pin connector? Clarify please.
Yes, most of my testing was with them connected to the same cable with the appropriate modifications
regarding speed, set in the scsi bios.

Yes, "TERM PWR EN" - I did try both enabled and disabled - but I tried so many combinations,
honestly, I lost track long ago.

-tw

OK.. found it - here is my card:
http://www.adaptec.com/worldwide/pro...+HBAs+%26+RAID
(although I didn't pay anything CLOSE to the $329 they are saying it costs!)

1 68-pin conecter is labled LVD/SE, and the other is labled SE.
I currently have my 160 drives conncted to LVD/SE. And yes, as you mentioned, I found in some
adaptec doc's that I should not connect less then160 drives to the same channel. But no matter what
I connect to the SE channel (the 160's or 80's), I get a termination error.

I'll pick up a proper cable with a built in terminator monday and see how it goes.
thanks again randyding
-tw

LVD needs a cable with the terminator because the U160/U320 drives do not supply termination, SE drives on the other hand have terminator jumpers on the drive and should not be terminated at the cable.
I just can't remember if the U2W (80mb/s) is single ended or LVD. If its LVD then you're in worse shape because you can't connect them to either bus. One bus will have to be for the 160s and the other bus can't be used because its for single ended drives only. Some drives will switch into a single-ended mode if connected to a single ended card, but not all drives support this and I've had drives that claim to support both LVD and se and don't work correctly on se.

Oh, so you have the 29160 card. That should be an okay card to use. So does that card work in a 32bit pci slot or are you running 64bit in that machine.

My Fujitsu drives (here are the specs: http://www2.fcpa.fujitsu.com/sp_supp...-datasheet.pdf ) - its a pdf by the way)
are 80MB/sec LVD.

The label on the drive say:
Ultra 160 SCSI/68-pin/LVD

So... as you say, I'm in worse shape now then before. ( ??? ). I'll try a better (terminated cable) and see what
happens - I hope I won't have to trade them in for more 160's.

And about the card - yeah its a really nice one, especially compared to my 2940 - but its only in a 32bit PCI slot. (not enough cash to get a new board yet)

I'll post back with updates/more info
thanks agian
-tw

randyding,

Just for the info - I picked up a proper 68-pin cable w/ LVD terminator. All 4 drives
are running great on the same channel. I did some benchmark testing of the 160's
before I connected the 80's. There were no problems detecting any of the drives, and
the benchmarks were not decreased by having the 80's on the same channel (the LVD
channel) as the 160's.

Thanks a lot for your help.
-tw

Good to hear its working. Before the OS boots, what does the scsi bios print out about the bus speed. Does it say 160/160/80/80 for the drive speeds?

Yes, and the same goes for linux when it loads the scsi card, 160/160/80/80.

I don't claim to understand it, as this is exactly what Adpatec told me NOT to do .
but who am I to question success??

-tw

p.s. - Have you used Bonnie and/or Bonnie++ to benchmark your drives?
I read that they are more accurate then hdparm on scsi . I'm having trouble
comparing the bonnie results to hdparm's. Just wondering.

But I can sure tell the difference in speed with the new drives & controller!