Path: utzoo!mnetor!uunet!husc6!bbn!mit-eddie!bloom-beacon!gatech!ncar!noao!mcdsun!mcdchg!clyde!mtunx!whuts!homxb!homxc!rps
From: rps@homxc.UUCP (R.SHARPLES)
Newsgroups: comp.sys.ibm.pc
Subject: Re: 3.5 inch and 1.44 Meg
Message-ID: <2085@homxc.UUCP>
Date: 4 May 88 18:45:37 GMT
References: <983@tjalk.cs.vu.nl>
Organization: AT&T Bell Laboratories, Holmdel
Lines: 30
Keywords: 3.5 inch 1.44 Meg FORMAT.COM, doesn't work
Summary: Yes, you need DOS 3.3

In article <983@tjalk.cs.vu.nl>, se6@cs.vu.nl (Houweling E) writes:
> I've just installed a 3.5 inch, 1.44 Mb disk drive in a XT clone 
> with DOS 3.2. 
> The drive works all right, but FORMAT.COM formats it at just 720 Kb and 
> refuses to give me the full 1.44 Meg capacity. 
> (Yes, I used high-density disks) The manuals gave no answers, so I'm stuck.
> I wonder if maybe DOS 3.3 is needed for those high-density 3.5 disks ??

Yes, DOS 3.3 is needed.  Microsoft as well as many hardware vendors will
tell you flat out that DOS 3.2 won't support 1.4 meg format.  Some drives
come with a CONFIG.SYS device driver that will allow 1.44 meg format
but this driver generally costs $100 - $150.  For $120, DOS 3.3 is a 
better deal.

HOWEVER! You must be sure that your controller will support 1.44meg.  The
standard XT controller will not!  Just like an XT controller won't support
1.2meg 5.25" drives, it won't support 1.44meg on 3.5" drives, even if 
the disk drive will.  The controller must send a special command to the
drive to switch it into the higher density mode.  A number of companies
make disk drive controllers that support this, COPY II PC Deluxe Option Board
comes to mind, SYSGEN, Tigertronics also.

Russ Sharples
homxc!rps

NOTE:

The above in NO WAY reflects the opinions of AT&T.
These opinions are my own and the results of un-scientific and 
highly irregular analysis methods.