Extended BIOS translation (worth disabling?)

[Peter Holzer]

On Wed, Feb 04, 1998 at 05:50:26PM -0600, Rob Browning wrote:

> I currently have translation enabled, which, as I understand it, means
> that the drives appear to have a different geometry than they actually
> do so that DOS can access drives > 1GB.

No. You always have some translation enabled, and the BIOS never sees
the real geometry of the drive. The difference between "normal"
translation and "extended" translation is that the first uses 32 sectors
and 64 heads, while the second uses 63 sectors and 255 heads. Since the
BIOS can only handle 1024 cylinders this gives you a maximum disk size
of 1GB and slightly under 8GB respectively. 

>   1) Is there any benefit (performance or other) from the unix
>      perspective to turning the option off?

No.

>   2) If I do turn it off, will I still be able to use the drives from
>      Win95, as long as I keep the DOS partitions under the 1024K
>      boundary on each drive?

I think so (haven't tried it, though). If Win95 uses its own drivers
instead of the BIOS, you would also be able to access partitions beyond
the 1024 cylinder boundary, you just cannot boot from them.

	hp

-- 
   _  | Peter J. Holzer             | If I were God, or better yet
|_|_) | Sysadmin WSR                | Linus, I would ...
| |   | hjp at wsr.ac.at               |     -- Bill Davidsen
__/   | http://wsrx.wsr.ac.at/~hjp/ |        (davidsen at tmr.com)
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