As I remember, most of HD with this legend "master=on, slave=off", means that you can remove the jumper for a slave disk.

I saw on Seagate, and Samsung Disks

Excellent point -- I missed the obvious there, but believe that to be correct, and also valid on Maxtor HDDs I have used in the past.

Hi,

The IDE drive jumpers will depend on drive manufacture. Most set the Master/Single with no jumper. Then for multiple drives you would select a Master/Slave with a jumper setting. You should google for the drive manufacture & model to get the jumper table settings. If you use the 'cs' then the position on the cable will decide device assignment. Some manufactures provide a jumper table physically on the drive. You might find a mask labeling on the PCB of the drive.

OP, you seemed to have a contention problem. The device jumpers were not set properly, if you want a Master/Slave then set the jumpers properly. Place the Master at the end of the cable.

If the drive is a current IDE then be sure to use a '80 conductor' cable, place the index (red/blue stripe) pointing to the power supply connector, most new drives have a key on the connector to prevent the connector from being placed incorrectly.

A lot of drives will default to slave if the master jumper is not set. Many drives do not include a jumper to set for slave - they assume if master is off, slave is on, with CS being the exception to the rule.

Thank you for the advice. I found these:
http://www.seagate.com/images/suppor...5_family_1.gif
instructions for the jumper settings and just removed the jumper from the slave drive (which is SEAGATE,ST3160812A).
Actually the drives' jumpers were set properly previously. In fact the only change I made was to put the drives at their correct places on the 80-conductor cable. So far after several reboots things seem to be ok. Time will show.

Thank all of you for your responsiveness and collaboration.

Regards,
Martin