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I have reinstalled Windows 7 on my Dell Precision M4600. I installed the chipset (restarted), then video and network driver (in that order). However I am not able to dim the light using fn-up/down.

I installed the drivers first without any Windows update. Using the control point software, I got the little dialog showing the dimming. However after updating the dialog displays but it is fixed; that is, nothing happens when I try to dim the screen. The keyboard dimming works.

I am having NVIDIA 1000 Quadro M graphic card if that is any help. Turning off Optimus in BIOS fixes the problem but I have never had this problem before reinstalling.

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Did you reinstall from a recovery partition or CD? If from a CD, did you install all the drivers that should have come with the laptop? I normally get a drivers and utilities CD from Dell. If you didn't get one, try – Bob May 1 '12 at 8:50
For the record: This is not allowed. You should only ask your question once. If you have any details to add, click the edit link. This will even bump the question to the front page. If you still think your question deserves more attention, consider placing a bounty. – slhck May 1 '12 at 9:22

You're missing dell system software. Go to, choose one of the three options on screen, then click "Drivers & Downloads" or the like, then enter your service tag (found on the underside of your laptop), then you'll likely want to select "All files for ... " that's in about the middle of the screen, refine the search results it gives by selecting your OS, under the title of "System Utilities" you should see something similar to "Dell Feature Enhancement Pack". This is what you want to download and install.

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It does not work when nVidia Optimus is enabled, why so? – Andy Apr 27 '12 at 17:23
If I answered your question please mark it as answered. If you have another question either edit your post or make another post. (And be more specific, I'm not sure I know what you're asking w/ this question) – jhstuckey Apr 27 '12 at 17:36
It's called "Dell Feature Enhancement Pack", as stuckey said. The M4600 is one of the most complicated systems to install drivers for, and I've setup 100s of servers, DAS units, etc. I seriously cannot believe the amount of drivers available, and the order you need to install things with. – Eric Duncan Jun 18 '12 at 20:55

I have run into the same situation with my Dell M6600. Suddenly the dimming stopped working, I still got the popup icon on the screen though. After some testing, I found that I needed the Intel video driver from the Dell site to make it work. The Intel driver I had downloaded from Intels site doesn't support this feature. I am only guessing, but it could be the same situation for your model too.

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+1. Win7 M4600 with a screen that wouldn't dim or brighten with the hotkeys - installing the older Intel GMA HD driver from the Dell site did indeed fix this! For those wondering, specifically I went to the Dell support site, entered my service tag, selected Windows 7, and selected Intel_multi-device_A09_R307994.exe driver to download. After you download this, you have to unzip it to a temporary folder, then run setup.exe found in that temporary folder. This will require a restart afterwards. – Thorin Aug 27 '12 at 4:59
Almost four years later and I was having this problem again after updating the built-in graphics driver. If you want to be able to dim the screen using the Fn key and the Up Arrow / Down Arrow keys, while also having Optimus enabled for the discrete graphics chip, you need Intel_multi-device_A09_R307994.exe, found here:… – Thorin Apr 11 at 16:27

On most laptops this is built into the BIOS and never requires a driver. In the rare occasion such as yourself, you will likely need to install their keyboard utility (or utilities) specific to that model. It looks like they made that functionality the same as other model-specific keyboard shortcuts.

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This is usually called a 'hotkey' driver or something to that effect. – Shinrai Apr 27 '12 at 15:55
@Shinrai I am not able to find it :( – Andy Apr 27 '12 at 16:48

According to the Dell Re-Image Guide it appears you need to install either the "Control Point System Manager" or the "Dell Feature Enhancement Pack – DFEP"

DFEP is Windows 7 only.

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Thanks, I installed Control point system and it works now, but it won't dim the screen when I press fn+up/down. It only shows the message on the screen. I am going nuts of this soon. – Andy Apr 27 '12 at 17:13

You can roll back the drivers, or reinstall the drivers now that your updates are done. In fact, Go directly to NVidia and either have it detect your chipset, or pick the most up to date drivers you want to install. There are a couple of options for Quadro (ODE, Performance, etc). You will always get the latest drivers from NVidia, as opposed to Windows Update.

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I think the dimming may be done by special keyboard shortcut like Fn + Arrow Down or UP. Check your keyboard and see something like that.

Updating your video driver is of course must be done too.

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Dell recommends the following sequence for driver istallation:

  1. System Software
  2. Chipser
  3. Video
  4. Network Interface
  5. QuickSet/Control Point
  6. Audio
  7. Modem (if applicable)
  8. Wireless network card
  9. Touchpad, pointer, trackstick, keyboard/mouse.
  10. Other (Intel AMT, Bluetooth, Mobile Broadband, PCMCIA/Smartcard, TouchScreen, etc.)
  11. OPTIONAL: Update/Flash the BIOS
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Can you add a source? – bwDraco Sep 29 '12 at 19:10

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