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2237
June 14th, 2023 13:00
optiplex 7400 display brightness unable to change
Hello,
On a Dell Optiplex 7400 AIO that was upgraded by us to Win11, we are unable to figure out why the display brightness cannot be changed. The slider on Windows settings does nothing, and Dell On-screen Display (OSD) doesn't seem to function on it.
List of what I've attempted:
-updated drivers and bios
-updated windows 11 to latest
-attempted to install Dell OSD
-verified Windows power settings
Any help would be much appreciated
No Events found!
adamm
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June 20th, 2023 05:00
Solution Found:
My searches were focused on the immediate problem, but my colleague remarked how there were a couple BIOS updates that wouldn't install. He looked up a solution to that, which also solved the On-screen display.
-In Device manager go to System Devices tab
-Uninstall all Microsoft Windows Management Interface for ACPI (there's ~10)
-As well as Microsoft System Management BIOS Driver.
-reboot
-Then Dell command update
Unfortunately I do not recall which BIOS update version it was, but this oughta do the trick.
This solved the issue on both Windows 10 and 11 versions of the Dell optiplex 7400.
Chino de Oro
9 Legend
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8.1K Posts
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June 15th, 2023 20:00
Dell On-Screen Display (OSD) allows you to control the brightness bar, change the input source, and turn the screen on or off through the OSD button.
If Dell OSD application did not work for you, that left with not much to try with.
You may try to create a high performance power plan using Control Panel. Then check the brightness slider again, from system tray.
bradthetechnut
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9.1K Posts
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June 20th, 2023 12:00
I'm glad you found a solution. : ) If you go into BIOS it should tell you what which version it's on.
Chino de Oro
9 Legend
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8.1K Posts
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June 20th, 2023 13:00
Although it was worded in a different way, the solution was found after OP repeated the same attempts: power (ACPI), BIOS, and Dell OSD.