Laptop LCD screen turned completely white:
What can you do if the laptop LCD screen turned completely white? From my experience I can tell that this problem may be related to the following:

1. Loose connection between the video cable and the LCD screen.

2. Defective LCD screen.

3. Defective motherboard (I assume the graphics card is integrated into the motherboard).

Here’s an example of a laptop with white screen. When you turn on the laptop, it starts but the image on the screen is completely white right from the beginning. In my case it was a Toshiba Satellite M45 laptop but this problem may occur with any other brand.






Most likely you still can use the laptop with an external monitor. Just connect the monitor to the VGA port on the back or side of your laptop and then switch the video output from internal to external mode.

On Toshiba laptops you can toggle between internal and external screens using Fn+F5 keys. Hold down Fn and press on F5 until you get video on the external monitor.

On IBM laptops use Fn+F7.

On HP laptops use Fn+F4.

It’s possible that you have to use a different key combination on your laptop but you get the idea.

On some laptops, in order to be able to use the external monitor, you have to connect it to the laptop and then restart the laptop so the external monitor is detected by the laptop.

I noticed that in some cases the laptop screen may turn white because of poor connection between the video cable and the LCD screen. If you want to check this connection, you’ll have to take apart the display panel because the connector is located on the back side of the LCD screen.

These laptop service manuals and disassembly instructions may be useful.

I always check the video cable connection first. Reconnecting the video cable may fix your problem.

If reconnecting the video cable doesn’t help, most likely you have a problem either with the LCD screen or with the motherboard.

The best way to find out witch one is causing the problem is testing the laptop with another working LCD screen. Without this test you’ll have to guess because as I mentioned before this could either bad motherboard or bad LCD screen.

You’ll have to disconnect the video cable from the LCD screen (connector 2) and the inverter board (connectors 3 and 1). After that you connect another working screen and test video.

For this purpose I’m using one of my test LCD screens. My test screen is cracked and because of that you see a wide white band in the center but it still works fine for this test.

The original screen is white but my test screen works normal (except the crack of course) and I can see the image. After this test I can tell that the problem must be related to the screen.

After I assembled everything back together and connected the original LCD, it’s still white.
CONCLUSION. In my case this problem is related to the LCD screen and it has to be replaced.

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The Windows Blue Screen of Death (BSOD):
Ah— the dreaded Blue screen of Death. When your windows operating system crashes, you will get the dreaded Blue Screen of Death, which is a stop error. Only, in this case, it means that your operating system has totally crashed.
Most people don’t realize that the Blue Screen of Death is actually a protective mechanism that the operating system uses to prevent irreparable damage to the system files by immediately shutting down the entire system the instant it discovers a critical system error. If it shuts down fast enough, damage will be avoided. If not, you could end up having to reinstall your operating system depending on what caused the error. The picture below shows a BSOD error.

What Causes the BSOD Error?

The primary causes for BSOD errors are:

• Poorly written device drivers. In this case you should update your drivers.
• Malfunctioning hardware such as bad memory, power supplies, overheating, etc
• Two applications attempting to write to the same memory location simultaneously because a record lock failed
• Invalid / corrupt registry entries. You can repair this with a good registry cleaner.

When the encounters a fatal error, it will send diagnostic information to the display screen right before it reboots the system. In many cases, the reboot will clear the problem and the system will run normally.

What Does All That Stuff on the Screen Mean?

Each stop error is paired with a description of theerror and an eight digit hexadecimal error code number. You can use thisinformation tofigure out what is ciausing the problem. Let’s dissect the error screen above. A copy is shown below.

In the first red box, it says that the spcmdcon.sys file has cause a PAGE_FAULT_IN_NONPAGED_AREA. That is the type of error the system encountered. This error occurs when the data requested from memory by the processor cannot be found at the location address provided. This can be caused by defective RAM including main memory, video RAM, L2 or L3 cache, etc.
The second red box contains the technical information about exactly what memory locations are involved.

Can You Fix a BSOD Error?

In the case above, there is a good chance that one of the memory modules has some bad blocks. Even if the machine reboots and runs fine, you should get the memory tested and replace it if necessary or at least use a repair utility that can mark the block that are bad so the system doesn’t use them again.
If there is nothing wrong with the hardware and the problem keeps reoccurring, you will need to do an operating system repair using the repair console or you can just reinstall the operating system.
Some Common BSOD Errors are:
IRQL_NOT_LESS_OR_EQUAL – a kernel mode process tried to access restricted memory, which means memory reserved for processes that have a higher IRQL level than it does.
KMODE_EXCEPTION_NOT_HANDLED – an illegal or unknown processor instruction was encountered
PAGE_FAULT_IN_NONPAGED_AREA – the requested data could not be found at the supplied address

INACCESSIBLE_BOOT_DEVICE – the system cannot access the boot sector which usually means there is a hard drive disk  problem or a boot sector virus.
UNEXPECTED_KERNEL_MODE_TRAP – caused by defective or mismatched memory, a bad CPU or a bad CPU fan and the processor  is overheating
DRIVER_POWER_STATE_FAILURE – caused by a defective device driver
THREAD_STUCK_IN_DEVICE_DRIVER – a bad driver is causing an infinite loop
NTFS_FILE_SYSTEM – the file system is not working properly
UNKNOWN_HARD_ERROR – one of the registry hives could not be loaded into memory usually because of a hard disk failure or a corrupted registry hive
STATUS_IMAGE_CHECKSUM_MISMATCH – usually caused by a damaged paging file but can occur for other reasons

Conclusion

The BSOD, especially if it reoccurs, usually means there is a serious problem that will eventually require you to replace hardware or to reinstall the operating system. In fact, many times it may be necessary to do both … replace the faulty hardware and then reinstall the operating system.

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I picked up 3 laptops yesterday.

The first laptop was a Gateway laptop that has a dc power connector. This will take approximately 2 hours to fix. In addition, the customer was not able to connect to his wireless network so I will have to fix this after the connector was fixed.

The 2nd laptop was a Dell 1521 that had a very pale image on the screen and no backlight. The customer stated that the bottom portion of the screen got very hot and then the light went out. 90% of the time this is an inverter issue and the the other 10% is a bad screen. With the inverter being the cheapest component, this is always the first item to try.

The 3rd laptop was an acer that had a broken screen. I always like hearing the stories about how the lcd screen was broken. Ive heard everything from the customer stepping on the computer to it getting hit with every object under the sun. In this case, it was an elbow that took out the screen. A cracked screen is usually indicative of a spider web fracture pattern across the screen and multiple lines and colors not normally seen. Some of the screen still works but regardless it needs replaced.

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Laptop screen shows strange colors. What could be wrong?:
Laptop screen started showing strange or wrong colors. What could be wrong? I’ve been asked this question many times and today I’m addressing the issue.

In this post I explain some basic troubleshooting techniques in case if your laptop screen started showing strange or incorrect colors.

You have to know how to disassemble the laptop in order to use following troubleshooting techniques.

TEST LAPTOP WITH EXTERNAL MONITOR.

The main step is testing how laptop outputs video on an external monitor (or TV).

You can connect your laptop to an external monitor using VGA cable, DVI cable, HDMI cable or S-Video cable, it depends on a type of connector you have on the laptop. Most laptops have VGA connector, so it would be the most common way to connect.
In my example I’m connecting to an external monitor via VGA connector.

Some laptops detect external monitor automatically and start showing image on both screens right from startup.

Other laptops can detect the monitor but display image only on one screen (internal or external). In this case you’ll have to switch video between internal and external using the Fn key and one of the F* keys in the top row of the keyboard. This combination varies for different laptop brands, for example it’s Fn+F5 for Toshiba, Fn+F4 for HP, Fn+F8 for Dell, Fn+F7 Lenovo etc…

WHAT VIDEO ON EXTERNAL MONITOR CAN TELL?

If both, the internal screen and external monitor (or TV) show strange or incorrect colors or any other image distortion, this is the graphics card failure.

If only the laptop screen shows strange colors or any other distortion but external image appears to be normal (as in my example), the problem is somewhere inside the laptop display. It could be bad connection, bad LCD cable or bad LCD screen.
Let’s narrow down the problem one by one.

TRY RESEATING LCD CABLE CONNECTOR ON MOTHERBOARD.

The laptop screen receives data signal from the motherboard via LCD cable. If the LCD cable not making good connection with the motherboard, it might cause image or color distortion on the screen. Try reseating the LCD cable connector and see if it fixes the problem. Make sure the LCD cable connector plugged correctly.
In most laptops the LCD cable connector located under the keyboard bezel (aka keyboard cover). If it’s not there, most likely you’ll find it somewhere under the keyboard.

WIGGLE THE LCD CABLE.

The LCD cable runs inside the laptop display, under the LCD screen. For this test it’s necessary to disassemble the display, so you can access the cable.

A pinched or damaged wire inside the LCD cable also can cause color distortion.

Try wiggling the LCD cable while the laptop is running. If wiggling the LCD cable affects image on the screen in any way (it starts shown different colors, lines, or image clears to normal, etc…) most likely the LCD cable is defective and has to be replaced. Try replacing the cable.

On the other hand, if wiggling the cable doesn’t affect image on the screen at all, most likely the cable is good and your problem related to the LCD screen failure. In this case you’ll have to replace the LCD screen.

APPLY SOME PRESSURE TO THE DISPLAY.

Try applying some reasonable pressure to the top part of the display assembly. Squeeze it with your fingers.

If the screen starts showing different colors, lines, or clears to normal when you squeeze the top part of the display panel, most likely this is LCD screen failure. In this case you’ll have to replace the LCD screen.

Also, you might be interested in the following posts:

Troubleshooting laptop with backlight failure.

How to test LCD screen inverter in a laptop.

Laptop has bad video on the LCD screen. What is wrong?

How to troubleshoot and fix laptop video problems.

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