Installing a second IDE (PATA) hard drive: what must you do before attaching it on the same cable as the first drive?

Introduction / Context:
Older IDE (PATA) interfaces allow two devices per channel on a 40/80-conductor ribbon. Correct jumpering prevents bus contention and ensures the BIOS recognizes both drives correctly.

Given Data / Assumptions:

• Two PATA drives on one IDE channel (one cable).
• Traditional Master/Slave or Cable Select options available.
• Standard PC BIOS detection for PATA devices.

Concept / Approach:
With Master/Slave mode, the second drive must be jumpered to Slave and the first to Master. Alternatively, with Cable Select (CS) both drives are set to CS and cable position determines role, but the question implies the classic Master/Slave practice.

Step-by-Step Solution:

Verification / Alternative check:
On POST, both drives should enumerate. The OS disk manager will show both devices; drive letters are assigned by the OS, not set in CMOS directly.

Why Other Options Are Wrong:

• IDE configuration software: Not required for basic jumpering.
• Define as D: in CMOS: CMOS does not assign letters; the OS does.
• End connector only: Not mandatory; middle connector works, especially with CS cabling.

Common Pitfalls:
Mixing CS and Master/Slave modes, wrong jumper settings, and using 40-wire cables with ATA modes needing 80-wire cables.

Final Answer:
Set the master-slave jumper to slave on the second drive