Troubleshoot Stop 0x9F or 0xFE on AMD-Based Windows 7/Vista PCs (Historical)

Historical support note: Windows Vista support ended in 2017 and Windows 7 support ended in 2020.

The original article grouped 0x0000009F and 0x000000FE together as an AMD EHCI problem. That is too broad. Microsoft defines these as two different bug checks:

0x9F — DRIVER_POWER_STATE_FAILURE: a driver is in an inconsistent or invalid power state.
0xFE — BUGCODE_USB_DRIVER: an error occurred in a USB driver.

An older AMD-based PC could encounter either code around standby, resume, or USB activity, but the code alone does not prove that the AMD chipset is the cause.

If the crash happens during sleep, resume, or shutdown

For 0x9F, concentrate on devices and drivers involved in power-state transitions:

Note what changed before the crashes began: a new device, driver, firmware update, or power-management utility.
Check Device Manager for devices reporting problems.
Install the chipset, USB, storage, graphics, and other relevant drivers supplied for the exact PC or motherboard model.
Check the PC manufacturer’s support page for BIOS/firmware updates that mention power, USB, sleep, or resume problems.
Review the System event log around the time of the crash.

If the crash points to USB

For 0xFE, disconnect non-essential USB devices and test again. Then reconnect devices one at a time to isolate the trigger.

If one USB controller or hub is repeatedly implicated, updating the chipset/USB controller driver is preferable to disabling power management across every USB root hub.

The old Microsoft Fix it link referenced by the original article is no longer a supported troubleshooting path and has been removed.

About the USB power-management checkbox

On some legacy systems, temporarily clearing Allow the computer to turn off this device to save power for a specific USB hub can help confirm a suspend/resume interaction. Treat this as a diagnostic workaround, not a universal repair.