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Windows 7/Crazy horizontal lines on screen


Upon turning on my Acer today there were squiggly lines running horizontally across the screen like one might see across and old static tv set. I didn't wait to see what else would happen, just pushed the off button; the screen went black,but the power light remained on. Pushed the power button a few more times, nothing changed = power lights on, screen black. Next I unplugged the laptop,= light stayed on & screen still black. Finally I removed the battery, power light went off, yeah!

Waited a few minutes & restarted laptop in safe mode, no problem. Turned it off then restarted in normal mode, no problem.
How do I check further as to what possibly caused the initial problem? Thank you for any help you can give me; I'm basically a beginner.

Hello Christine

First of all let me say you did everything correctly with regards to fixing the problem. That being said you should know a few things. As you are now wondering what the problem was, sometimes it is best to just say "why ask why" when the problem is fixed.. but that being said, you can do a few things to possibly prevent this from happening again.

For starters, you should know that with any computer (laptop or desktop), if/when you can't move the mouse or the keyboard is frozen, pressing AND HOLDING the power button until the computer shuts off is how you go about shutting it off. What you did by pressing the power button simply placed the computer in a low-powered state, such as 'standby' or 'hibernate' where there is still power flowing through the motherboard and memory. By pressing AND HOLDING the power until all the lights go out, that tells you that it is off. However, in your case because you have a laptop, you did the right thing by also unplugging the battery.  This is something you should always do to ensure you have killed ALL POWER, and should probably leave the battery unplugged for at least a minute or more to allow the capacitors to completely discharge.

Next, you went in to windows safe mode once you plugged everything back in. This is also a good thing because by going to safe mode you can at least be assured that the computer is functioning properly, with regards to the screen coming on normally (or somewhat normally as it only loads the basic display driver so things will look big and blotchy) Also by going to safe mode after a failed boot up attempt will allow the computer to reset any failed driver installs. Therefore once you restarted it normally, if all looks fine then that is because all the drivers loaded correctly.

Now, you want to know why this happened and what you can do to prevent it...

Basically the system didn't load the display driver from the sounds of your description. Either that or it was getting low power to the memory which can cause all sorts of strangeness including what you saw. This can happen when there was an automatic windows update which may have included a display driver update, and/or other integrated driver such as network or chipset driver that either didn't completely overwrite the old driver or was corrupted due to your system possibly being shut down in the process of this automatic install. What you should do now is confirm that you have ALL windows updates up to date by going to windows update and choosing all optional items as well, not just the critical ones.

Your antivirus program may have also been in the process of downloading or updating the virus definitions or it had also a corrupted install which can cause what you saw. The fact that when you went in to safe mode all was working, you know your windows drivers are working. Antivirus and networking don't work in safe mode so if you still had troubles when it booted normally that would be something to check on.

You should also be making sure your system is free and clear from the malware/spyware issues including items that start on windows start up that could also be causing drivers to not load correctly. For this I suggest using two programs.   The first is CCLEANER which you can download from the following website:

Then to learn how to use this program to its optimum potential visit the following website:

The second program you will want to use is malwarebytes which you can get from the following website:

You can learn how to use malwarebytes from the following website:

One thing I always suggest with these programs is to go in to the preferences and turn off the 'monitoring' settings as I only like to use these programs as tools to clean and optimize my systems and not have them run all the time and monitor because that simply slows your system down. If you run these weekly (or more if you are doing a lot of web surfing) then that should be good enough so no need to have them running on start up and monitoring.

I hope this helps clear things up a little for you.


Mike Dacre
follow me on twitter @tpsconsulting

Windows 7

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Mike Dacre


As I have been volunteering in the 'windows' category since the inception of AllExperts, which has now moved to numerous windows categories. I will therefore be happy to answer any Windows 7,8 and 10 based question. What can't I answer? Not much, as this is the main reason I volunteered here, because I am hopeful the questions I can not answer will allow me to investigate the problem so that I can answer it. The TIPS and SOFTWARE support through my website at can also be of some help.


I have owned my own computer consulting business for the past 17 years and since the very beginning I have volunteered with AllExperts in the hopes I would be able to learn from others mistakes and problems. The goal for me is to be able to research any problem I don't initially have the answer to, in the hopes I will be able to further benefit for my own clients when they come across a similar problem.

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I grew up with computers, from the first Apple IIC, back when Bill Gates was a student himself! For the past 17 years I have been providing technical services from building computers to constructing complete control rooms. Working with CTV I have helped produce the 1994 Olympic Games in Lillehammer, Norway. Later, designing and construction of "instant replay control rooms' for the Big Screens found in Stadiums and Coliseums.

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