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When I put my laptop to hibernate or sleep while plugged in and I resume from hibernate or sleep on battery, the backlight is off. A faint image exists on the display, but is nearly impossible to read, suggesting a video driver problem. When I change GPUs using AMD PowerXpress switchable graphics, the backlight comes back on. Why would this occur, and how do I fix it?

The system is a custom-built HP Pavilion dv6z-3000 Select Edition laptop with Windows 7 Home Premium. There are two GPUs on this system, an ATI Mobility Radeon HD 4250 for low power and an ATI Mobility Radeon HD 5650 for high performance. The system is running an OEM version of the Catalyst drivers that appears to be version 10.3, based on the internal version number supplied by HP. Would I lose any OEM features in upgrading the Catalyst drivers (which may be necessary to fix the problem)?

Edit: I've updated Catalyst, and the problem seems to be gone. I can't say for sure at this time, so I'm not posting this as an answer. I'll update the question as needed. If anyone can reproduce this, let me know.

Edit 2: Unfortunately, the problem still recurred on me at least once. What exactly is the problem?

Edit 3: This problem only occurs when the system is set to use the high-performance HD 5650 GPU. PowerPlay is disabled. Any ideas? The problem is still unresolved.


For now, an answer will remain accepted, but if anyone can give a better answer, I will gladly accept the better answer.

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Is the problem always on the same adapter? What power options do you have on it? –  harrymc Jun 9 '11 at 18:57
    
Can you clarify what you mean by "adapter"? –  DragonLord Jun 9 '11 at 20:45
    
By adapter I mean the video card or GPU, meaning the device as seen by Windows. The power options can be found from Device Manager. –  harrymc Jun 10 '11 at 6:48
    
There are two display adapters as listed in the question. The Mobility Radeon HD 4250 has no special power options; the Mobility Radeon HD 5650 has AMD PowerPlay available and enabled. –  DragonLord Jun 10 '11 at 14:12
    
Does the problem happen only on the AMD ? –  harrymc Jun 10 '11 at 18:09
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3 Answers

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+50

The article Brightness control after resume sleep/hibernate broken seems to show that this is a universal problem with Win7 across many laptop models.

Some suggestions from the article are :

  1. In Power Settings the "Choose what the lid does" is set to do nothing, then close the lid and re-open every time this happens
  2. Press Fn+F7 (select projector mode) then select "computer only"
  3. Ensure that you are logged-in as administrator
  4. Uninstalling the monitor device (NOT display adapter) in Device Manager and then scanning for devices again.
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My laptop does not have a projector mode button; I use the Windows-P shortcut for this purpose. However, this does not fix the problem. Thanks for the link, and I hope Microsoft fixes this problem. –  DragonLord Jun 12 '11 at 16:18
    
I assume Win-P can be substituted in your case instead of Fn-F7 in other laptop models. If you will try this and the other ideas, it might be interesting to know if one of them does work for you. –  harrymc Jun 12 '11 at 16:23
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Many bad video drivers have this problem. If fact many other device driver also have problems resuming from sleep etc.

One rough solution is to use Microsoft DEVCON to reboot the device driver

In Windows you can schedule a task to run after a resume event

Use devcon hwids * > ids.txt to get a file of all id's, find you vidoe cards id

Use devcon restart yourvideoid

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The devcon solution worked for a dell M6700 with a K5000M video card. Make sure the task is run as SYSTEM The action for this video card was C:\Windows\System32\devcon.exe restart *DEV_11BC* after copying devcon.exe into the system32 dir.

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