[comp.sys.ibm.pc.hardware] Help on partitioning hard disk

cobb@petsd.UUCP (Chris Cobb) (07/30/90)

Keywords:

I'm having problems partitioning a hard disk, and hopefully someone can
show me the error of my ways. I have an AT compatible running MS/DOS 3.3
with a 40MB hard disk as drive 0. I used to have a 20MB hard disk as drive
1 (worked with no problems), but I just replaced it with an 85MB
(unformatted) disk. The disk has 9 heads and 1024 cylinders, and my BIOS
supports it. I have two separate formatting programs which both format the
disk with no problems.

When I tell FDISK to allocate the largest primary DOS extent it can, it
allocates 428 cylinders for the extent (31MB and some change). When I tell
FDISK to allocate an extended DOS extent, it allocates 1022 cylinders for
the extent, with each logical drive being allocated as 428 cylinders. So
far, so good. The problem is when I run FORMAT against any logical drive
on that disk, FORMAT replies, "Invalid partition table/Format aborted".
FDISK now reports that the disk contains no active partitions. For
chuckles I tried allocating an extent of 200 cylinders, and that formatted
fine. I did not have enough time to play around to see how many cylinders
I could specify before FORMAT would barf.

I heard that version 4.01 of MS/DOS does not limit the partition size of
hard disks. Is this my answer, or is there something else I may be
missing? My experience tells me I should not be having this problem in
the first place. Any suggestions would be greatly appreciated.
-- 
+==================================+==========================================+
| UUCP: {att,princeton}!petsd!cobb | What's another word for "thesaurus"?     |
| or    cobb@petsd.tinton.ccur.com |                       -- Steven Wright   |
+==================================+==========================================+

chaz@chinet.chi.il.us (Charlie Kestner) (08/02/90)

In article <1840@petsd.UUCP> cobb@petsd.UUCP (Christopher B. Cobb) writes:
>Keywords:
>
>I'm having problems partitioning a hard disk, and hopefully someone can
>show me the error of my ways. I have an AT compatible running MS/DOS 3.3
>with a 40MB hard disk as drive 0. I used to have a 20MB hard disk as drive
>1 (worked with no problems), but I just replaced it with an 85MB
>(unformatted) disk. The disk has 9 heads and 1024 cylinders, and my BIOS
>supports it. I have two separate formatting programs which both format the
>disk with no problems.
>
>When I tell FDISK to allocate the largest primary DOS extent it can, it
>allocates 428 cylinders for the extent (31MB and some change). When I tell
>FDISK to allocate an extended DOS extent, it allocates 1022 cylinders for
>the extent, with each logical drive being allocated as 428 cylinders. So
>far, so good. The problem is when I run FORMAT against any logical drive
>on that disk, FORMAT replies, "Invalid partition table/Format aborted".
>FDISK now reports that the disk contains no active partitions. For
>chuckles I tried allocating an extent of 200 cylinders, and that formatted
>fine. I did not have enough time to play around to see how many cylinders
>I could specify before FORMAT would barf.
>
>I heard that version 4.01 of MS/DOS does not limit the partition size of
>hard disks. Is this my answer, or is there something else I may be
>missing? My experience tells me I should not be having this problem in
>the first place. Any suggestions would be greatly appreciated.

  Compaq DOS 3.31 will solve your limitation of 32M/partition in DOSs
under 4.01.  It will allow 512M partitions.

brim@cbmvax.commodore.com (Mike Brim - Product Assurance) (08/03/90)

In article <1990Aug02.052158.2497@chinet.chi.il.us> chaz@chinet.chi.il.us (Charlie Kestner) writes:
> In article <1840@petsd.UUCP> cobb@petsd.UUCP (Christopher B. Cobb) writes:
> >Keywords:
> >
> >I'm having problems partitioning a hard disk, and hopefully someone can
> >show me the error of my ways. I have an AT compatible running MS/DOS 3.3
> >with a 40MB hard disk as drive 0. I used to have a 20MB hard disk as drive
> >1 (worked with no problems), but I just replaced it with an 85MB
> >(unformatted) disk. The disk has 9 heads and 1024 cylinders, and my BIOS
> >supports it. I have two separate formatting programs which both format the
> >disk with no problems.
> >
> >When I tell FDISK to allocate the largest primary DOS extent it can, it
> >allocates 428 cylinders for the extent (31MB and some change). When I tell
> >FDISK to allocate an extended DOS extent, it allocates 1022 cylinders for
> >the extent, with each logical drive being allocated as 428 cylinders. So
> >far, so good. The problem is when I run FORMAT against any logical drive
> >on that disk, FORMAT replies, "Invalid partition table/Format aborted".
> >FDISK now reports that the disk contains no active partitions. For
> >chuckles I tried allocating an extent of 200 cylinders, and that formatted
> >fine. I did not have enough time to play around to see how many cylinders
> >I could specify before FORMAT would barf.
> >
> >I heard that version 4.01 of MS/DOS does not limit the partition size of
> >hard disks. Is this my answer, or is there something else I may be
> >missing? My experience tells me I should not be having this problem in
> >the first place. Any suggestions would be greatly appreciated.
> 
>   Compaq DOS 3.31 will solve your limitation of 32M/partition in DOSs
> under 4.01.  It will allow 512M partitions.

From the comments above it appears that you have a 40meg as drive 0 and an 
80meg as drive 1.  Is the 40meg drive still bootable and working? Are all
problems occurring only on the 80meg drive?  If so why after allocating 428 
cylinders in FDISK did it then allocate 1022 for the extended partition (I'm
thinking outloud to myself)? Also, what are the two formatting programs you
used?  Are you loading a device driver that installs partitioning information 
(such as Disk Manager)? If so and you need it for the 40meg, partition the 80meg
with it as well.  Or back up the 40meg, and use the DOS FDISK to partition
both drives.

The sernario you listed should cause no problems with the tools you (MSDOS 3.3
FDISK, and FORMAT) have.  The 1024 cylinders fall within DOS's capibility.
The 80meg drive should be first low-level formatted with your formatting 
utilities, then have FDISK partition it.  Make sure that you select option
5 to switch to drive 2 then go through the appropriate selections of Create
DOS Partitions...   

As for Compaq 3.31, while the info is correct, it may be impossible to obtain.
Your 3.3 should work or if you feel the need, try MSDOS 4.01 or (yipes)
PCDOS 4.0.  Better yet, if you get your system up with 3.3 wait till DOS
5.0 appears (probably before the end of the year).  Having used it, I know 
it will be worth the wait.


--------------------------------------------------------------------------------
I only talk for myself and have problems doing that.

Mike Brim	PC Analyst
Product Assurance		
Commodore Electronics Limited		West Chester, PA 19380 
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