In Windows Vista, an Ultra DMA Mode 5 device may perform only at the speed of an Ultra DMA Mode 2 device after you swap devices.

This problem occurs on an IBM ThinkPad mobile PC or on a Lenovo ThinkPad mobile PC if the following conditions are true:

• You start the computer with an Ultra DMA Mode 2 device in the Ultrabay swappable drive bay. For example, you start the computer with an optical drive in the drive bay.
• You eject the Ultra DMA Mode 2 device from the drive bay and insert an Ultra DMA Mode 5 device in the drive bay. For example, you insert a hard disk drive in the drive bay.

When these conditions are true, the transfer mode stays at the slower Ultra DMA Mode 2 speed. The system does not correctly use the faster Ultra DMA Mode 5 speed.