Consider the following scenario:

• On a ThinkPad X300 computer that is running Windows Vista, you enable the Disable optical drive option on the Power Management tab.
• You leave the system idle for more than 10 minutes, and the optical disk drive turns off.
• You perform a suspend-and-resume cycle or a hibernate-and-wake cycle on the computer.

In this scenario, the computer’s optical disk drive is intermittently not displayed in My Computer or in Device Manager.