Windows 7 Won't Detect My Primary Monitor

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  1. Posts : 9
    Windows 7
       #1

    Windows 7 Won't Detect My Primary Monitor


    I'm using a Sager 3790 notebook with 2 GB of memory, a Centrino 1.7 Ghz and a Mobility Radeon 9700.

    Installation went perfectly. The card was detected by Windows Update and drivers were isntalled for it. They're from December 2008. Okay, that's fine and dandy... BUT...

    As soon as the drivers install the highest resolution available on the primary display is 640x480. Why? Because Windows won't/can't detect my primary monitor. It shows up as an "Unknown display device."

    I can attach an external monitor and adjust its resolution all day. I can also remote into the laptop and that works fine.

    I am nearly 100% confident that I cannot change the display resolution because the monitor won't detect correctly. I can't manually force an install of a monitor or change the "Unknown display device" driver because that section is grayed out in the "Advanced Settings" under the Display Resolution tab.

    Any ideas?
      My Computer


  2. Posts : 1,009
    Windows 7 RC 7100 32bit/64bit
       #2

    Under Device Manager, can you uninstall the monitor and reboot so it's re-detected again?
      My Computer


  3. Posts : 9
    Windows 7
    Thread Starter
       #3

    The laptop's monitor doesn't actually show up under the Device Manager so there is nothing to remove or configure. If I uninstall the video drivers then the monitor shows up as "default monitor." If the display drivers are installed it disappears and any reference to a monitor is called "Unknown display device."
      My Computer


  4. Posts : 202
    Windows 7 Ultimate 64bit
       #4

    Just to clarify, are your video card drivers installed correctly?

    I get the same issue as you are when I was on XP installing new nvidia drivers, they installed into the wrong directory, but once I pointed windows to the correct location it resolved itself.

    If it is the monitor for sure, you might try manually pointing windows to the "windows" dir, it should find the base driver for the OS and fix the issue.

    Side note: what monitor model is it?
      My Computer


  5. Posts : 9
    Windows 7
    Thread Starter
       #5

    angryman said:
    Just to clarify, are your video card drivers installed correctly?

    I get the same issue as you are when I was on XP installing new nvidia drivers, they installed into the wrong directory, but once I pointed windows to the correct location it resolved itself.

    If it is the monitor for sure, you might try manually pointing windows to the "windows" dir, it should find the base driver for the OS and fix the issue.

    Side note: what monitor model is it?
    The video card drivers are installed correctly.

    Let me clarify. We're talking about the LCD on the laptop. The LCD is not incorrectly getting identified. It's not getting detected at all. There is no wrong monitor to force a driver change to. There's no monitor at all. It is acting like Windows doesn't know it exists when the graphics drivers are installed.

    If I uninstall the video drivers then Windows detects the video card as a default display adapter with up to 1440 x 1050 display resolution or something like that; the generic driver with no acceleration. At that point the monitor is then also detected as a "default monitor" and I can change the resolution. As a side note, I'm not able to change the driver of "default monitor" either. Those setting tabs are grayed out.
      My Computer


  6. Posts : 202
    Windows 7 Ultimate 64bit
       #6

    Ah, I see now!

    You are not alone with this issue, try this:

    Hook up your external monitor, then hit your mode switch button, it should bring your LCD back.... in your bios, change the default monitor setting.

    See if that works... your LCD might go blank again if you reboot, so you might have to access your bios with the external.
      My Computer


  7. Posts : 9
    Windows 7
    Thread Starter
       #7

    angryman said:
    Ah, I see now!

    You are not alone with this issue, try this:

    Hook up your external monitor, then hit your mode switch button, it should bring your LCD back.... in your bios, change the default monitor setting.

    See if that works... your LCD might go blank again if you reboot, so you might have to access your bios with the external.
    Hitting my switch mode button doesn't do anything. The external monitor is identified (when you hit the "Identify" button) as "1." With an external monitor hooked up, only one monitor is recognized at all to exist; just the external one. I can change its resolution, it is accelerated; everything works.

    Changing the BIOS settings from LCD/CRT/LCD+CRT are the only options I have. I've tried all three extensively with different combinations of drivers and external monitors.
      My Computer


  8. Posts : 202
    Windows 7 Ultimate 64bit
       #8

    Sorry, I am half asleep, I was looking to solve a "blank" or dead LCD off your laptop, but I re-read that its displaying at 640x480 at least.

    I've been checking around and does not seem to be a common issue, it's obviously the drivers, even though you say they are correctly installed (I thought mine were when it was stuck in 640x480, but redirecting fixed it, but I guess if you are sure?), if you have not resolved this by the time I wake up I will take a look before work, with a fresh mind.
      My Computer


  9. Posts : 9
    Windows 7
    Thread Starter
       #9

    angryman said:
    Sorry, I am half asleep, I was looking to solve a "blank" or dead LCD off your laptop, but I re-read that its displaying at 640x480 at least.

    I've been checking around and does not seem to be a common issue, it's obviously the drivers, even though you say they are correctly installed (I thought mine were when it was stuck in 640x480, but redirecting fixed it, but I guess if you are sure?), if you have not resolved this by the time I wake up I will take a look before work, with a fresh mind.
    I haven't solved it yet.

    Here's what I've found out at this point. It's almost certainly a driver issue and I have a feeling there isn't going to be a solution for this. In Windows XP, the only way I could get this notebook to show the correct resolution was to hard install a monitor driver and then uncheck "show compatible modes." It wouldn't detect the correct highest resolution as compatible even though it was.

    I don't think I have that option. As far as I can tell, there's no way in Windows 7 to install a device that doesn't exist.

    I'll be watching this post for a few more days if anybody comes up with any other ideas. If not I'll just drop XP on there again and call it good enough.
      My Computer


  10. Posts : 202
    Windows 7 Ultimate 64bit
       #10

    Make sure you send a feedback report (top right of current open window, including IE8), microsoft does listen.

    Radeon should be listen as well, do they not have beta drivers for windows 7 yet? I know nvidia does.
      My Computer


 
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