Phoenix BIOS, hard disk data loss

sd xscd at
Thu Dec 4 15:52:33 PST 2003

On the chance that this information might help someone else.

Some months ago, just after buying a Tyan Tiger s2466 MPX dual processor 
motherboard and installing FreeBSD 5.0 on it, I experienced a lot of 
data loss (lost files and directories, unrecoverable by fsck). I 
thought the problem might be related to disk geometry (I'm fairly new 
to FreeBSD and the sysinstall disk geometry warning concerned me).

However, after a couple months I decided to change just one setting in 
the Phoenix BIOS: Large Disk Access Mode

There are two options for Large Disk Access Mode: "DOS" and "Other"

The help text for this item says: "This option denotes that a hard drive 
with more than 1024 cylinders, more than 16 heads and or more than 64 
tracks per sector is present. Choose OTHER when using OSes such as 

So, at first I had chosen "Other." However, after all the data loss, I 
felt I had nothing (more) to lose so I changed it to DOS just to see if 
it made a difference. Apparently it did. I have experienced no more 
lost data (from hard disk corruption or problems) in the six or so 
months since I made the change.

Maybe this will help someone else. Thanks,

Steve D

Good luck favors the bold and confident, and if one shrinks
from fear of adventure, then fate conspires to provide
adventure to one in their hiding place.

More information about the freebsd-questions mailing list