Secondary IDE controller does not work due to unrecognized IDE controller chip.

Cause:

Windows 95 (version 4.00.950) may not recognize the Intel 82371SB PIIX3 IDE controller on Intel motherboards, causing the BIOS to disable the secondary IDE channel. The results can be that devices are not being detected or disappearing after the system is rebooted.

Solution:

Contact Intel for the appropriate utility to update MSHDC.INF.