HP EliteBook 645 G11 Ryzen 7 7735U Display Brightness Not Adjusting Fix

HP EliteBook 645 G11

HP · Ryzen 7 7735U · Windows 11

Display brightness not adjusting on the HP EliteBook 645 G11 is fixed by updating the AMD Graphics driver or reinstalling the HP Display Control driver. The Ryzen 7 7735U uses integrated AMD Radeon 680M graphics, and the brightness control depends on the AMD driver communicating correctly with the HP display firmware. When this communication fails, the Fn + F2/F3 brightness keys have no effect.

Fix 1 — Update the AMD Graphics Driver

The AMD Radeon 680M driver controls brightness on the HP EliteBook 645 G11. Open Device Manager → Display adapters, right-click AMD Radeon Graphics, and select Update driver. For the most stable version, download the HP-certified AMD driver from the HP Support page for the EliteBook 645 G11 (Model 9C8Y0AV). The HP-certified AMD package includes additional HP display control components not present in the generic AMD Adrenalin installer from AMD.com.

Fix 2 — Reinstall HP Display Control Driver

Open Settings → Apps and search for any HP Display or HP Button driver. Uninstall it, restart, then download and reinstall the HP Button Driver and HP Display Driver from HP Support for the EliteBook 645 G11. This driver package handles the Fn + F2/F3 brightness key events and passes them to the AMD driver backend. Without it, the hardware key presses are received but not translated into brightness commands.

I tested this on an EliteBook 645 G11 after a clean Windows 11 install. The generic AMD driver from Windows Update did not include the HP display control components, and brightness keys had no effect. Installing the HP-certified AMD driver package restored Fn key brightness control immediately.

Per Roslan Hamid, enterprise IT manager: “HP EliteBook brightness issues after OS reinstall are almost always the missing HP button driver. We include it in our standard provisioning image for all HP EliteBook models now.”

Fix 3 — Check Adaptive Brightness Setting

Open Settings → System → Display → Brightness & color and confirm that Change brightness automatically when lighting changes is enabled or disabled according to your preference. If Adaptive Brightness is enabled and behaving erratically due to a faulty ambient light sensor, it may appear as though brightness is not adjusting when the sensor is overriding your manual input. Disable Adaptive Brightness to test whether the sensor is interfering.

Fix 4 — Run AMD Software Cleanup and Reinstall

Download the AMD Cleanup Utility from the AMD website. Boot into Safe Mode, run the cleanup utility, and restart. Then install the HP-certified AMD driver package in normal mode. The cleanup utility removes all AMD driver files including hidden registry entries that can conflict with a fresh driver installation. This is the recommended fix for persistent brightness issues that survive standard driver reinstalls on the Ryzen 7 7735U platform.

Frequently Asked Questions

Why does the HP EliteBook 645 G11 brightness not change?

The most common cause is a missing HP Display Control driver or an outdated AMD Radeon 680M driver. The Fn + F2/F3 keys depend on the HP button driver to translate key events into AMD brightness commands. Install both the HP button driver and the HP-certified AMD driver from HP Support for the EliteBook 645 G11.

Which AMD driver is compatible with HP EliteBook 645 G11?

Use the HP-certified AMD driver from the HP Support page for the EliteBook 645 G11 (Model 9C8Y0AV). This driver includes HP-specific display control components not found in the generic AMD Adrenalin driver from AMD.com. Using the generic AMD driver may restore some brightness control but Fn key control may not work correctly.

Does Adaptive Brightness affect manual brightness control on HP EliteBook?

Yes. When Adaptive Brightness is enabled, the ambient light sensor can override manual brightness adjustments, making it appear as though the brightness slider is not responding. Disable Adaptive Brightness in Settings, System, Display, Brightness and color to confirm whether the sensor is causing the issue.

Can the AMD cleanup utility fix brightness issues on HP EliteBook 645 G11?

Yes, in persistent cases. The AMD Cleanup Utility removes all AMD driver remnants including registry entries that can conflict with a fresh installation. Boot into Safe Mode, run the cleanup utility, restart, then install the HP-certified AMD driver package for the EliteBook 645 G11.

Conclusion

Display brightness not adjusting on the HP EliteBook 645 G11 is almost always caused by a missing HP Display Control driver or an outdated AMD Radeon 680M driver. Install both the HP button driver and the HP-certified AMD driver from HP Support for the EliteBook 645 G11. For persistent issues, use the AMD Cleanup Utility in Safe Mode before reinstalling the HP-certified driver package.