VGA+Plugged in produces screen flicker

Whenever I have my laptop plugged into the power adapter and external LCD (Samsung 216bw), the lcd monitor will flicker like crazy. These are horizontal lines that run up and down the face of the monitor.

Now, the thing is it only happens when the computer is plugged in. On battery, the problem is solved, which points to an electrical disturbance problem.

I'm on a U300-AY1. Anyone else find these issues, or better yet, find a solution?

 

I used to get those flickers when my cable was too long, but went away when I bought a shorter 6 ft one. I don't know why it would go away when you're using your battery though.

 

Thats why i'm thinking its electrical disturbance caused by the system, not by the wires. It doesn't happen on my desktop, nor my old XPS (same monitor hooked up).

 

Is your power cord/adapter a two prong ungrounded one or a three prong grounded one? If it is a two prong one, then that may be your problem.

-J.B.

 

3 pronged grounded one. I also had this same issue on my Vostro 1310. That one, had the issue with the 3 pronged adapter, and NO issue with a 2 pronged adapter. Insanely queer. does toshiba sell 2 pronged adapters that work with the U300?

 

It's this type of problem. Also, discussed in this thread.

You could try using a power socket strip with surge suppression and noise filter, or plug the computer and monitor into separate wall outlets. Otherwise you need to break the earth loop. One fix is to disconnect the earth wire from the power plug. You could buy a news mains lead, chop off the existing plug and fit a new one with the earth (green/yellow striped wire) cut off.

Here is a stack of Toshiba PSUs. Most / all have 2 pin mains leads. I got a 45W PSU for my R500 to replace the 60W monster when came with the notebook. It arrived within 2 weeks or order. 2/3rd of the cost was shipping but the bottom line was still reasonable compared to buying a Toshiba PSU in UK (and 45W is not available).

John

 

FLICKER BE GONE!
I'm so glad I found this forum today. I have a new external Acer X183H 18.5" monitor I'm using with a 6 month old HP/Compaq "Presario" laptop.

I've had the identical problem to the person above who experiences constant monitor flicker when his laptop is plugged into an AC outlet, but he finds the flicker disappears completely when the laptop is unplugged and running on battery. Exactly my situation too.

Thanks to the person who suggested simply plugging the laptop and the monitor into separate wall outlets. I tried that and it worked like a charm!
I now have my laptop plugged into a surge protector connected to one wall outlet, and my external monitor plugged into another one, connected to a 2nd wall outlet. What ever interference existed before that caused the irritating flicker effect is finally gone. THANKYOU!

 

Im also glad I found this post today.I have just bought a dell 2209wa 22" monitor which is really really good,however I too am getting some kind of flickering interference (when conected to my laptop vga output).I was worried that would have to return the monitor.
I have now narrowed it down to the power supply,as the flickering stops when Im running the laptop from the battery.I have tried plugging the power supply into a seperate socket but this doesn't work.I may have to try a surge suppression socket and see if that helps.
I am happy its not a fault with the monitor,so thanks to evryone in this post.