Screen flashing white

Is there a good image on an external monitor when the fault shows on the internal one?

i dont have an external monitor, so i dontknow. ive run every hardware/software check i can think of... do you think it could be a bad connection somewhere inside the laptop?

CAGW

If you don't have access to an external monitor you can try the BIST test.  When the problem happens next, shut the system down and restart it while holding the F2 key.  Diagnostics will start, if you can see the screen you will notice video diagnostics. Press N when the video diagnostics ask if the video test ran correctly. After pressing N, the screen may start flashing solid colors. If it does then there is no problem with the LCD.  

If the screen is white while running diagnostics you may not see the system running diagnostics,  you should hear an warning beep or siren. When you hear the warning siren press the N key.  Then check to see if the white screen goes away and it starts flashing solid colors, this again is an indication that the LCD is fine.

Otherwise this is a problem with the video adaptor.  If the problem happens while diagnostics are running then the video adapter will be defective and you will likely need to replace the system board and processor.  If the diagnostics ran fine and you noticed no problems but they continue in Windows then I suggest reinstalling the video driver from the following link.

<ADMIN NOTE: Broken link has been removed / replaced from this post by Dell>

TB

thanks for the reply.

i ran the tests with no problems.

so i downloaded the driver you linked to - but i haven't installed it because i get a message saying 'the computer currently contains driver versions newer than the versions you are about to install.'are you sure you want to overwrite etc etc'.

i'm guessing i'm right not to install it?

If the diagnostics looked good and you saw the flashing colors after pressing N then it is likely a problem with the video adapter.  The current driver may be corrupted. Download the driver from the link and save it on the desk top. Then I would uninstall the driver. Go into Programs and features and uninstall the Intel video driver. Don't allow the system to restart when it asks but once it has been removed shut the system down manually. Start the system up while tapping F8 and choose "low resolution mode" and log into windows.  Decline any prompts by Windows to install a driver.  Then execute the downloaded driver.  Once that has been installed restart when requested by Windows and see if the system continues to flash.

TB

thanks again for the help, i'll try that

Only thank me once this gets resolved.  Please let me know if reinstalling the driver helped.

TB

I have the same problem. But the image on external monitor is good when there is flashing white screen on internal LCD. I ran the BIOS test, the result is pass. But I think it should pass, because everytime I restart the laptop, the white screen will disappear. So after I turned off the laptop and restarted it, the LCD test should be fine. All the drivers, BIOS are latest. What is the problem?

Yih

This is what I understood from your post, that sometimes the LCD on the notebook flashes, you have tested this with an external monitor and the image on the external monitor is good even though the internal LCD flashes, is this correct? If so then this implies that there is a problem of some short with the LCD, it could simply be that the data cable doesn't have a good connection and needs to be reseated.

You also mentioned that the internal monitor doesn't flash while in the BIOS, that you don't have a white screen while starting the system is this also correct?  This on the other hand implies that this is a software issue with Windows or the video driver.  The confusing thing about this is that if the video driver is corrupted then the external monitor should have the same problems as the internal screen does.

I suggest running diagnostics and perhaps we can get more information what is going on here.  Start the system holding down F2, just press and keep pressing F2, holding the button down while starting the notebook.  Diagnostics should start, allow all of diagnostics run and see if at any time the screen flashes white or if you get error messages.

If you can see the contents of the screen start the system and tap F12 and choose diagnostics and allow the test to run. If the image looks good the entire time then the LCD is likely fine, and has no defects.  If the screen flashes white running diagnostics allow the diags to continue, eventually an alarm will sound, when it does press the letter N and see if the screen starts flashing different colors or continues to flash white.  Please report back and let me know what you find.

TB

Yeah that error message was caused by pressing N, if you got solid flashing colors after pressing N then LCD is fine.  This implies the problem is with the video card or drivers.  Since diagnostics looked good, it implies the problem is with the video driver.  I suggest uninstalling the video driver. First download the latest video driver from support.dell.com and save it to the desktop.  Go into programs and features (add remove programs) and uninstall the video driver, don't restart when prompted and manually shut down the notebook.  Restart the system tapping F8 and choose "enable low resolution mode (VGA mode)" and boot to Windows.  Decline any prompts from Windows in reinstalling the video driver and manually install the driver that you downloaded. Follow Windows prompts this time.  Reboot and see if the problem has gone away.

TB

I ran the diagnostics again by holding the Fn while not F2. For the video part, the screen displayed two pages solid color bars (horizontal and vertical, looks good) and I can hear the warning beep. I then press N when the video diagnostics ask if the video test ran correctly. After pressing N, the screen started flashing solid colors. But at last, I got error codes.

error code 334, Msg error code 2000-334. I am not sure if this is because I pressed the N.

I don't think it is the driver issue. Because 1. I just updated the driver 3 months ago. 2. As you said, if the video driver is corrupted then the external monitor should have the same problems as the internal screen does. 3. this problem happens frequently when the weather is hot. I will try to reinstall the driver anyway and report the result later (this problem doesn't always happen, so I have to wait).

In addition, I think the diagnostics can't detect every problem. For example, if the problem is bad connection etc., the LCD can work well most time. If you test it when it works well, the diagnostics won't say anything. But actually, it is a hardware problem.

I wasn't so much worried about the diagnostics, only the BIST test. This is a test that only runs when you press N when diagnostics asked you if the graphics test ran correctly.  Once you press N, the BIST starts and changes the signal from the video adapter to the LCD directly.  If you saw the solid flashes of color after pressing N that states that the LCD is running correctly, as the signal for the test flashes came directly from the LCD.

As I said this is confusing because the results from the tests are contradicting each other.  A system that is able to show a good display on an external monitor while the internal display is just a white screen should never be able to pass the BIST test. But this is what is happening.  You mention that the problem happens more often when the weather is hot, is this correct?  Then that changes the story, if the system is cool enough the problem doesn't happen and we can't trust the diagnostics.  When the problem does occur, the external monitor works fine, the problem is only with the LCD.  Then that may well be a problem with the data cable not being connected well. I suggest resetting the data cable to the LCD then and see if that helps.

TB

I will try this. Although it is a hard work and may cost 1 hour.