Signal noise when connecting VGA and AC adapter at vaio z

Hi, I need to know if this is a issue with my vaio z or with all of them...

I've connected my vaio to the AC adapter, put it on speed mode and then connected my monitor... But there's like a LOT of noise, it-s like the white is moving...

I've tried changing the resolution and refresh but it's still with that noise...

Then I tried disconnecting the AC adapter and the noise suddenly stoped, and the image become clear and sharp....

Is anyone else having this problem??

I've bought the laptop yesterday and I'm planning to go ask my money back if they can't fix this.

 

Try a better VGA cable.

 

Also, are you connecting vga directly or through a keyboard/monitor switch (KVM)?

Mine looks clean when connected directly, and shows significant noise when going through a KVM switch.

 

Looks like you have a ground loop. You can try not grounding your laptop by using a ground adapter or using a 2 prong cord. Yes, there is a very minute danger to running ungrounded. Very minute. I run with a 2 prong cord when I travel overseas since many of the outlets aren't grounded anyways and it's sometimes hard to use a grounded plug. If that clears up the problem then you have a ground loop.

 

How ground works depends a LOT on where you are.
In the US, homes generally have single-phase electricity with neutral shorted to one of the other wires (TN-C network).
In many other countries, homes generally have a three-phase electrical system with neutral often being separate
In some parts (like in some parts of UK), neutral is earthed (true ground or "safety ground", IT network)
In other parts (like in Norway), neutral is grid-wide (floating ground, TT network).
In either case "ground loop" doesn't make sense.

(For more information, see http://en.wikipedia.org/wiki/Earthing_system)

But anyhow, it may not be a ground fault but transformer noise or other RF noise on the grid. In which case looping the power cable between the power supply and computer 2-3 times through a ferrite bead should take care of the problem.

 

Wow, I'll be trying that... Anyway it may be a poor quality cable (stock vga cable of dell monitor),
because I can't see noise when using a projector that have a better quality cable (or at least seems like a better quality cable).

Thanks =D

 

I just bought a vaio z and I noticed the same problem. When the power adapter is connected to the laptop, my monitor flickers. It didn't do this with my other laptops (dell and hp).

Piluex, did you ever fix this problem with a better VGA cable? Anyone else have this problem? What do you look for - for a "better" VGA cable?

Thanks!

 

i have this problem too.
my solution is to use an universal adapter as intermediate between wall socket and the ac adaptor plug.
just curious, is using HDMI eliminates the problem?
i got no hdmi to try.

 

Hi...!

I´ve recently bought a Vaio Z and have also the same problem... or quite similar.

I´ve got an old Samsung monitor that gives me no problem when conected to the VGA output from my old Compaq.

BUT when conected to de Vaio Z the signal of this monitor has got a little bit of anoying noise.

if I move the power cable conection this noise increase till stop moving.

Did some of you return your Vaio or did you find a solution?
So.... it´s a normal situation or do i return my laptop?

It´s my first time on this forum.
Anyway thankyou very much.

 

That's because that adapter is disconnecting you from the ground. This "noise" problem is a good o' fashion ground loop. I discussed it in post #4.

 

Anyway I can conect other laptop on the same place and I have no problem. It only happens with the vaio Z... and I percive this noise on the part of the screen with grey or dark colors...


Thank you very much people

 

Hi boys i´ve just tried with the HDMI in other monitor and this bad noise signal disapeared, but with the VGA the problem keeps on anoying me. I was in the hause of a friend of mine not in my house, so with another ground electric conection.