Win11Pro HP EliteBook 840 G5 brightness buttons not working

[Cubytus]

Hi,

I have this laptops with a freshly installed Windows 11 Pro copy. I also installed HP's Support assistant to automatically get the required drivers.

However, two problems remain:

1. the brightness buttons (F3 and F4) aren't changing the display brightness. The on-screen brightness indicator does show, but not the brightness per se. Same goes with the Windows-provided brightness slider. The night mode display doesn't act either, incidently.

2. In the Device manager, there's still "Other peripheral" that doesn't have a driver installed. Hardware identification number is:

PCI\VEN_8086&DEV_15D9&SUBSYS_00008086&REV_02

Now, I have checked very similar topic there, but this isn't the same issue. At the path described, there's nothing blocking any device installation.

These issues may or may not have something to do with one another.

Please advise

[Paul_Tikkanen]

Hi:

You need this driver for the hardware ID you posted:

Driver - HP EliteBook 840 G5 Notebook PC | HP® Customer Support

Did you install the Hotkey Support Driver?   That is supposed to work the Fn keys.

Driver - HP EliteBook 840 G5 Notebook PC | HP® Customer Support

[Cubytus]

Hi @Paul_Tikkanen,

as a matter of fact no, I only relied upon HP's own Support Assistant.

Now, the Missing peripheral issue is solved, but not the brightness bug. This isn't a hotkey issue.

[Paul_Tikkanen · Accepted solution]

Unfortunately, I wouldn't know what the problem is then if you installed the Inte chipset installation utility and the applicable graphics driver(s) for your notebook.

[Cubytus]

Actually no, the graphics card was using the basic Microsoft-provided driver. I manually installed the Interl driver you linked, and the basic functionality got restored.

Note to self: don't trust HP Support Assistant software

thanks!

[Paul_Tikkanen]

You're very welcome. 

Glad everything is working now.