PCI-Express: Officially abbreviated as PCIe (and sometimes confused with PCI Extended, which is officially abbreviated as PCI-X), is a computer expansion card interface format. It was designed as a much faster interface to replace PCI, PCI-X, and AGP interfaces for computer expansion cards and graphics cards.

When you wake a Windows Vista-based computer from sleep (S3), the computer may stop responding (hang). When this problem occurs, the screen first becomes black. Then, you may eventually receive a Stop error message that resembles the following:

*** STOP: 0×0000009F(parameter1, parameter2, parameter3, parameter4)
DRIVER_POWER_STATE_FAILURE

This problem may occur if the following conditions are true:

• The computer is using a PCI-Express (PCI-E) graphics device.
• The computer’s firmware grants native support to the operating system for PCI-E features.
• PCI-E Active State Power Management (ASPM) is enabled on the PCI-E graphics device.

This problem may occur intermittently.