Question about Dell Latitude C640 Notebook

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Display The colors on my display are inverted. Like on a negative picture, how do I fix this?

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Re: Display

Check my threads, I have explained how to adjust color, brightness, contrast etc thru display properties
My way is the easiest, you should be able to find this issue in my posts
if you can't, let me know-

Posted on Feb 28, 2008

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Re: Display

I have a c640 also but the the laptop is cool and the is inverted even at the bios/cmos i think ill open it up and see if the cord needs to be re-seated...

Posted on Feb 28, 2008

Re: Display

If you computer gets to hot it mess up things. don't use a computer on the bed it will keep the heat in the computer there are air ways under some laptops for the fan and if the fan can't blow heat out you laptop will soon have problems. One other thing, Laptops are not made to run like Desktops.

Posted on Aug 28, 2007

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Re: Display

Hi meganb, sounds like a display driver issue to me, try and download the latest most up to date video driver from this link and that should solve the problem good luck

Posted on Aug 19, 2007

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The colors of my laptop's sreen are inverted. I've tried everything I could think of (display settings, system restore,....), how do I fix this?

Click start control panel administration tools computer management device manager scroll to display adapters + to expand you might see a yellow question mark ? or exclamation mark ! or a red x right click select reinstall drivers You might need to upgrade your graphics card drivers. You might have to remove your graphics card to make sure the socket is clean restart your computer the reinstall it this should activate found new hardware wizard if your computer came with a mother board disk the drivers could be on it Click start control panel display desktop you can select a different desktop from the drop down list or a browse button where you can select different pictures this may vary depending on your operating system also you can change the settings for more or less pixels or from the drop down list pick the appropriate level of color range or troubleshoot also select advanced then general dpi normal , larger or custom settings
Always click APPLY after making any changes windows 7 Open Personalization by clicking the Start button, clicking Control Panel, clicking Appearance and Personalization, and then clicking Personalization. Click Window Color and Appearance. Under Window Color and Appearance, click the color you want, and then click OK. Note If you see the Appearance Settings dialog box instead of the Window Color and Appearance window, the theme might not be set to Windows Vista, the color scheme might not be set to Windows Aero, or the computer might not meet the minimum hardware requirements for running Windows Aero. For more information, see Troubleshoot problems with Windows Aero.

Feb 28, 2013 | Dell Latitude D820 Notebook

1 Answer

The colors on my laptop's screen are inverted, how can I fix this?

Both OS X and Windows have inversion options for their displays. Their meanings, on the other hand, differ with the operating system. An inverted display on Windows refers to the display actually being upside down, while an inverted display on the Mac refers to the colors being inverted. Either way, these options can hinder the use of your computer, for obvious reasons. Luckily, an inverted screen can be fixed quickly, on both Windows and OS X.

Right click on the Desktop and select "Properties." Click the "Settings" tab and then select "Advanced." Click the "Driver" tab and then "Graphics Properties." Press "Display Settings" and uncheck the "Enable rotation" option. Click "Apply" and then "OK." On Mac OS X Click the Apple logo in the upper left hand corner of the screen. Scroll down and select "System Preferences." Select "Universal Access" and click on the "Seeing" tab. Check the "Black on white" option and the display should return to normal. Close System Preferences to save the changes.

Feb 28, 2013 | Dell Latitude D820 Notebook

1 Answer

Display fades away and colores waile reading

Replace it with a new LCD Inverter, you can address the following issues:
Screen image, but the power light stays in
Dark display, but still readable
Flashing on and off of the screen between 1/2 to several seconds
The power indicator stays on, but no display and sound
Screen images, but LCD TV still has sound
Picture cycle on and off, as well as high-power LED lights
More information in:

Feb 26, 2013 | Toshiba Satellite PC Laptops

1 Answer

LCD screen flickering

Display Configuration A flickering screen may be caused by the computer detecting incorrect display settings as it starts or returns from sleep. It can also come from changes to the screen resolution settings caused by a new program or update installation. Verify screen resolution before assuming the issue is hardware related. Faulty Inverter Next to the display screen behind the plastic screen bezel is a small component called the inverter, which supplies power to the screen backlight. The flickering indicates the power is not reaching the backlight. To fix the issue, replace the inverter. Faulty Connectors The wires and cables traveling from the display around the hinges and into the motherboard tend to wear at the hinge area. Over time, the opening and closing of the screen causes this wear. The solution is to disassemble the plastic casing of the laptop, reorganize the cables so they have no interference from hinges, or replace the cables and connectors with new ones made specifically for the computer make and model experiencing the issue. b> Test an LCD Inverter An inverter is an electrical device on the bottom of your laptop screen. The job of the inverter is to convert DC electrical current to AC voltage to maintain power to the backlight lamp. If the display on your laptop is dark but working, odds are the inverter or the lamp are at fault. When troubleshooting monitor problems on a laptop, you may need to evaluate the inverter to determine which of the two parts is malfunctioning.

Remove the screen bezel on your laptop. The bezel is the piece of the computer casing that surrounds and protects the LCD screen. To remove the bezel, remove the screws around the screen. Bezel removal method may vary by model. Once the screws come out, the bezel should pop off. The inverter will be under the screen. Attach the positive probe (+) of a multimeter to the pin 1 on the inverter. The inverter has two connections, one on each end. With the laptop screen facing you, look at the left side of the inverter. Pin 1 is the top metal flange pointing to the right. Secure the negative probe (-) of the multimeter to any bare screw. There should be a screw securing the inverter to the laptop that will be perfect for the negative ground connection. Turn the laptop on to test the inverter. Turn the multimeter on and check the multimeter reading. If the display records voltage going to the inverter, such as 19 V DC, the inverter power supply is working. Turn the laptop off. Unplug the LCD inverter connection on the right side of the inverter. This disconnects the backlight from the inverter. Plug a working backlight to the connection on the right side of the inverter. Turn on the laptop. If the screen lights up, the backlight lamp is bad but the inverter works. If the screen remains dark, the inverter is bad.

Feb 25, 2013 | HP Pavilion PC Laptops

2 Answers

ALL of the displays on my laptop are inverted


If you are using Windows XP, please check the following:

Click Start-> Control Panel-> Accessibility Options

Click Display tab

Make sure that the check box Use High Contrast is not checked. If checked, uncheck it and click Apply and Ok

Let me know the results


Feb 21, 2010 | Toshiba Satellite M205-S3217 Notebook

2 Answers

My screen looks like a photo negative..I have a Toshiba Satellite.

Right click on your Desktop, click on Properties, then go to the Settings tab and set the color to 32 bit True Color.

It sounds to me like your display settings are set to monochrome/black and white.

Best Regards,


Jul 21, 2009 | PC Laptops

2 Answers


your laptop display mass color, it is not the issue of inverter.
there are two situations:
1) mass color you can not see any messages like letter or picture
2) mass color with some or any messages you can see.
above situations you need to check LCD sreen cable connection between LCD socket and the motherboard socket, plug back properly.if not fixed, there are some tips you may consider:
1) change the Ram if the display ram is not isolated.
2) the LCD cable damage need to change or
3) LCD screen damage need to change or
4) finally the motherboard display chips damage(rare)

May 07, 2009 | HP Compaq Presario V2000 Notebook

1 Answer

The display has dimmed, and looks washed out (faded)

You most likely have a defective CCFL backlight, it may have the following symptom:
  • Screen flashs on red/pink and off.
  • Picture stays on in red and slowly be come normal.
  • Picture flickering with dim display.
  • Picture flickering on and off.
All these symptoms indicate that the LCD backlight lamp (CCFL Lamp) has reached the end of the life and all you need to do is replacing the CCFL lamp

Connect an external monitor to your laptop and power it up, if you see the normal Windows images then the video card and laptop is OK and the problem is definitely the backlight.

Dim image and/or dark display on the laptop's LCD screen indicates a faulty LCD backlight and it could be the inverter that supplies high voltage to the CCFL lamp or it is the CCLF lamp is nearly burnt out or burnt out, most likely this is the case.
The inverter can be replaced easily but the CCLF lamp is more time consuming and requires soldering skills.
Check out for parts, repair service and DIY info.

Apr 05, 2009 | Toshiba Satellite 4010CDS Notebook

1 Answer

Screen colors inverted

If you or a friend can acquire an external monitor for a short while, you will be able to at least separate the problem into two areas; if the test monitor shows normal colors, then the display section of your laptop has failed. If the external monitor shows the same color problem, then the video processor has failed.
With this knowledge, you can start making calls or emailing to determine what the repair cost would be.
Since the video processor is probably a part of the motherboard, this might entail a motherboard replacement since replacing chips by hand that were installed by robots may not be practicable. If it is a display driver failure, the entire display might have to be replaced for the same reason as mentioned.
In my mind, the display replacement might be a tad less expensive but not by much.
There is a slim possibility that the driver software has gotten corrupted so if swapping displays still doesn't conclusively tell you where the problem is, you might try removing the driver from the Device Manager and rebooting. Win should 'find' a 'new device' and reinstall the driver.     

Oct 05, 2008 | Toshiba Satellite A100-S8111TD Notebook

1 Answer


try to remove ur display driver and reinstall it

Dec 03, 2007 | HP Compaq Presario V2000 Notebook

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