Mike Ruskai wrote in a message to Pierre Vandevenne:

 MR> I'm aware of that.  I'm still not clear on what happens
 MR> between 16MB and  64MB.  By pure design, it ought to go from
 MR> a 512 byte allocation unit  (between 16MB and 32MB) to a
 MR> 1024 byte AU (between 32MB and 64MB), then on  to a 2048
 MR> byte AU, and so on.  But I still don't know off hand what it
 MR> would actually be.  I suppose I could try to get one of the
 MR> old PS/2's  working to experiment.

This is from the OnTrack Disk Manager documentation:


PARTITIONS UNDER DOS 2.XX

PART  SECTOR      CLUSTER       CLUSTER         CLUSTER      CLUSTER
SIZE   SIZE        SIZE          SIZE            SIZE         SIZE
(MB)  (BYTES)      (DOS)    (ABSOLUTE MIN)    (MIN CHKDSK)   (MAXIMUM)

0-.262  512         512 BYTES     512 BYTES        512 BYTES    8K  BYTES
.262-1  512         1K  BYTES     512 BYTES        512 BYTES    8K  BYTES
1-4     512         2K  BYTES     1K  BYTES        1K  BYTES    8K  BYTES
4-8     512         2K  BYTES     2K  BYTES        2K  BYTES    8K  BYTES
8-16    512         4K  BYTES     4K  BYTES        4K  BYTES    8K  BYTES
16-32   512         8K  BYTES     8K  BYTES        8K  BYTES    8K  BYTES
32-64   1K          16K BYTES     16K BYTES        16K BYTES    16K BYTES
64-128  2K          32K BYTES     32K BYTES        32K BYTES    32K BYTES

Note:  DOS VERSION 2.XX HAS A 128 MB LIMIT PER PARTITION


PARTITIONS UNDER DOS 3.XX

PART  SECTOR      CLUSTER       CLUSTER         CLUSTER      CLUSTER
SIZE   SIZE        SIZE          SIZE            SIZE         SIZE
(MB)  (BYTES)      (DOS)    (ABSOLUTE MIN)    (MIN CHKDSK)   (MAXIMUM)

0-8     512         4K  BYTES     512 BYTES        512 BYTES    8K  BYTES
8-16    512         4K  BYTES     512 BYTES        1K  BYTES    8K  BYTES
16-32   512         2K  BYTES     512 BYTES        2K  BYTES    8K  BYTES


PARTITIONS UNDER DOS 4.XX AND LATER

          |              ** CLUSTER SIZES **
          |
Part size | DOS DEFAULT | ABSOLUTE MINIMUM | ABSOLUTE MAXIMUM
--------------------------------------------------------------
   0-16   |     4K      |       .5K        |       8K
--------------------------------------------------------------
  26-32   |     2K      |       .5K        |       8K
--------------------------------------------------------------
  32-64   |     2K      |        1K        |      16K
--------------------------------------------------------------
  64-128  |     2K      |        2K        |      16K
--------------------------------------------------------------
 128-256  |     4K      |        4K        |      16K
--------------------------------------------------------------
 256-512  |     8K      |        8K        |      16K
--------------------------------------------------------------
 512-1GB  |    16K      |       16K        |      16K
--------------------------------------------------------------

 
-- Mike


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