kdunn@lehi3b15.csee.Lehigh.EDU (Kevin Dunn) (02/01/91)
I am having a problem with a Miniscribe 3650 hard drive.
About 1.5 years ago, I bought a 286 system with a "65 meg HD" from UTI
(Uniq Tech). During the past year, I have had an increasing number of bad
sectors gradually appearing on the drive (especially the 1st 32 meg partition).
Periodically, I would do a low level format with Spinrite, and most of the
bad sectors would disappear: Even running Disk Doctor would not detect them.
Over the next few months, though, they would gradually reappear. Repeated calls
to UTI assured me that there was no mechanical problem: I returned the drive to
them and they tested it ok.
Last week I turned on my computer and nothing happened. Upon booting from
floppy, I discovered that the Partition table was gone. I did a straight DEBUG
low level format (Spinrite would not work), and restored the drive. Lo and
behold, the drive formatted to 42 megs, not 65! (I have since discovered that
the drive IS a 42 meg MFM drive that was formatted to RLL. The company WILL
NOT accept responsibility or replace the drive, which is an entire other story)
Anyway, 2 days later the partition table again was gone. I have tried 2 more
low level formats, with no success.
When I called the company, I was informed to change the information in
the formatter from 17 sectors to 26 when I reformatted. I did so, but now the
drive will work at ALL. Something in the CMOS translated 820 cylinders,
6 heads, 26 sectors to 970 cylinders, 6 heads, 17 sectors.
The Question (finally!) is this: does anyone have any suggestions? I
can send the computer back, but since the 1 year grace period is up, I'd foot
the bill for any repairs. It seems to me that the company is at fault: they
cheated on the drive, and now evidently the BIOS/CMOS can't even handle the
formatting required.
I would like to get the drive working again, even at 42megs, so if
anyone has any suggestions, please let me know.
thanks, and sorry for the long post...
Kdunn@lehi3b15.csee.Lehigh.eduwilker@gauss.math.purdue.edu (Clarence Wilkerson) (02/05/91)
Some disk controllers have a jumper to enable sector translation on the fly so that the drive will look like 17 sectors/track to the outside world. So it adjusts the number of cylinders up to account for the increased capacity.
watkins@sapphire.idbsu.edu (Chris Watkins) (02/05/91)
Well, I have a 3650 drive, running on a perstor card. <basicly RLL only 31 spt> It's worked for almost 3 years now.. If the drive formats with a standard MFM hd controller & works (wich is probably what the company did) (@42meg) but starts to screw up when running 65 megs youve spotted your problem <i suspect this is it> Some drive just Can't handle having 26 or 31 sectors per track they just are notaligned right, <your drive is a hair off> I have been able to prolong this problem with another 3650, Low level it with a MFM controller about 10 times. Then It should work better, but only for awhile. -- / -------------------------------------------------------------------------\ | Watkins@Sapphire.idbsu.edu | (o) (o) | one must remember if it wasn't for| |____________________________| /_\ | the 60's we wouldn't be here. | | Computer Specialties, Inc. | \_____/ |___________________________________/