c_s144010423@stat.appstate.edu (02/25/91)
Does anyone have any experience using a Seagate 84Meg scsi drive model 269n? I presently have a 157n and a Future Domain controller and am thinking of upgrading. Any comments on the MTBF or problems with the 269n? Thanks in advance, any info appreciated... Dave
norcott@databs.enet.dec.com (Bill Norcott) (02/27/91)
In article <1991Feb26.013737.16024@scuzzy.in-berlin.de>, src@scuzzy.in-berlin.de (Heiko Blume) writes... >c_s144010423@stat.appstate.edu writes: > >>Does anyone have any experience using a Seagate 84Meg scsi drive model >>269n? I presently have a 157n and a Future Domain controller and am >>thinking of upgrading. Any comments on the MTBF or problems with the >>269n? > I have been very satified with mine. It is very cheap in terms of $/MB. Using the Future Domain controller will yield the same transfer rate as the Seagate ST01... about 440 KB/sec. I have tried both. This is slow by SCSI standards but it is faster than most MFM drives, and come near the price/capacity in MFM. With the Adaptec 1542B controller, the transfer rate is much better... ~660 KB/sec with CORETEST. This is better than RLL disks. By the way, I feel that CORETEST is not a fair test for SCSI disks because it reads tracks whereas SCSI transfers by blocks, which may or may not span tracks. In real life, SCSI is considerably faster than indicated by CORETEST. The 1542B is not recommended for 1:1 interleave, they recommend 2:1. The drive does not seem to have track buffering, so it makes a difference. At 1:1 (with the ST01) it transfers at ~40 KB/sec... it is slipping 1:1 and having to make many spins. The 440KB/sec is at 2:1. With the Adaptec I have measured it at 1:1. I think the controller has track buffering which masks some of the effect of interleave, I will try 2:1 tonight and let you know. I have upgraded to a CDC Wren 3 (155 MB) but am keeping the ST296N. I feel it is the price/performance leader for < 100 MB. Abother possibility if you don't mind salvage is the Maxtor LXT100 which is 96 meg and IME is selling for 299. They have quicker access time. Bill Norcott
hdrw@ibmpcug.co.uk (Howard Winter) (02/28/91)
I have an ST 296n - although your posting said 269, I believe that's the one
you mean, since the the '96' indicates 96Mb unformatted ('2' means 5 1/4"
half-height) and it formats to 84Mb. I am using it with the Seagate ST01
controller card, which is an 8-bit card. The drive comes with software
installed on it, which needs to be copied onto diskettes, and the drive is
then formatted and the software reloaded.
I had no problems with the installation, but the formatting process does
not allow the interleave factor to be changed. It is set to 3:1 by the
software giving a transfer rate of 310K bytes/second. I believe that
the 8-bit controller would not be able to handle 2:1 or 1:1 interleave.
Coretest gives performance figures: Average seek time 31.5mS, track-to-
track seek: 10.8mS. Data transfer 310Kb/Sec, Performance factor 3.5 XT.
I have heard this drive described as 'famously brain-damaged' and that
it cannot be formatted at 1:1 interleave. I understand this is because
its SCSI controller (on the drive, not the card) cannot handle it.
I have had only one problem, that very occasionally it fails to power
up properly. A sharp thump to the front of the PC's case cures it,
which suggests that the heads are not moving from their parked position
(the drive auto-parks on power-down). This has only happened about 4 or 5
times, over several months, and could be due to the room being rather
cold.
Although the drive is very goods value for money, I am disappointed by
its performance limitations. A better controller would help, but I am
planning to upgrade capacity as well, and I looking at a Conner 200Mb
IDE drive, which seems to be good value and is very highly regarded by
net.people. I will keep the ST296n as a second drive, and use it for
storing little-used software (shareware that I haven't evaluated etc)
and at a future date may change the controller.
I don't know what your budget is like, but I would try to get the best
drive affordable, not just the best value per byte, which is why I got
the 296 in the first place. I don't regret buying it (about a year ago)
but nowadays there is better to be had.
All of the above is my own opinion, and as such may be rubbish!
Hope some of this is useful - good luck.
Howard.--
Automatic Disclaimer:
The views expressed above are those of the author alone and may not
represent the views of the IBM PC User Group.
--
hdrw@ibmpcug.Co.UK Howard Winter 0W21' 51N43'lar@pc.usl.edu (Robert, Lane A.) (03/01/91)
hdrw@ibmpcug.co.uk (Howard Winter) writes:
Coretest gives performance figures: Average seek time 31.5mS, track-to-
track seek: 10.8mS. Data transfer 310Kb/Sec, Performance factor 3.5 XT.
I have heard this drive described as 'famously brain-damaged' and that
it cannot be formatted at 1:1 interleave. I understand this is because
its SCSI controller (on the drive, not the card) cannot handle it.
I've been told that there are some firmware revs that don't work
properly at 1:1, but the one I have hooked to my Amiga works great at
1:1. It gives about 650KB/sec on reads, and 450-500KB/sec on writes.
I don't know what your budget is like, but I would try to get the best
drive affordable, not just the best value per byte, which is why I got
the 296 in the first place. I don't regret buying it (about a year ago)
but nowadays there is better to be had.
I'll second that thought. I purchased mine in September of 1989; at
the time it was the best/largest/fastest SCSI drive I could afford.
But now, there are better/larger/faster drives available for less
money. Seems like I remember reading that a Quantum 105 MB drive can
be had now for about $350 US; at that price I may just find the use
for one!
Lane
lar@usl.eduthoger@solan.unit.no (Terje Th|gersen) (03/05/91)
In article <1991Feb27.200007.2439@ibmpcug.co.uk> hdrw@ibmpcug.co.uk (Howard Winter) writes: [deletions] I had no problems with the installation, but the formatting process does not allow the interleave factor to be changed. It is set to 3:1 by the software giving a transfer rate of 310K bytes/second. I believe that the 8-bit controller would not be able to handle 2:1 or 1:1 interleave. Coretest gives performance figures: Average seek time 31.5mS, track-to- track seek: 10.8mS. Data transfer 310Kb/Sec, Performance factor 3.5 XT. I have heard this drive described as 'famously brain-damaged' and that it cannot be formatted at 1:1 interleave. I understand this is because its SCSI controller (on the drive, not the card) cannot handle it. I have had only one problem, that very occasionally it fails to power up properly. A sharp thump to the front of the PC's case cures it, which suggests that the heads are not moving from their parked position (the drive auto-parks on power-down). This has only happened about 4 or 5 times, over several months, and could be due to the room being rather cold. [and more deletions..] Hi! You can format the drive down to 2:1 using the program in the BIOS, or using Diskmanager with the /M option. I've used two of these drives, and they've worked at 2:1 in an AT-compatible as well as my current 386sx. I've used ST01 and ST02 controllers, both with BIOS-revs 3.0.0. I tried 1:1, but this did not work. I have, however, seen a post from a guy that claimed he got 1:1 from a ST296/ST01 combo in a 25MHz 386. As for the "not-starting-up-properly"-problem, one of my drives developed this problem after about a year of usage. It seemed to be related to the temperature of the drive. (In other words, if I'd left the window open, so the drive was chilled down to 10-15 deg. Celsius, I'd get the problem every time.) I "cured" the problem by leaving the computer on for a minute or so, and then rebooting. A few comments, not previously noted : The drives run *very* hot. In fact, after just a few minutes, they are almost uncomfortably warm to the touch. Secondly : noise.. Two of these starting up and going through their self-tests will, for example, require you to shout when using the telephone.. :-) -Terje -- ____________________________________________________________________________ thoger@solan.unit.no | Institute of Physical Chemistry THOGER AT NORUNIT.BITNET | Div. of Computer Assisted Instrumental Analysis | Norwegian Institute of Technology