NP700Z3A-S01DE Mini VGA Port Problem

Hallo everybody,

three people including myself bought a Samsung 700Z3A (NP700Z3A-S01DE) notebook. In addition we got the Mini VGA- VGA Adapter.

If we are using it without power supply two different external monitors we tested had a normal screen.

But if we connect the power supply to the laptop the both external monitor start flickering extremly.

No problem we have if we connect the laptops by a HDMI-cable to newer monitors.

Somebody else has this problem that the Mini-VGA makes trouble?
Maybe it's only a bug for the german laptop version.

Somebody has an idea for a solution?

Best regards

Spowi

 

Because the problem only happens when your computer is plugged into the mains power, I suspect that you have got a ground loop. VGA is an analog signal that is more vulnerable to some extra noise than HDMI's digital signal. Can you use a 2 pin plug adaptor for the computer (or the monitor) that doesn't provide earthing? Alternatively, try plugging the computer and the monitor into different wall sockets.

John

 

Hallo John,

yesterday I checked different wall sockets, also with a long cable to a different room. No one works. Finally I put it in a socket directly next to the actual one and it worked. By checking the wall socket I found out that the little metal parts for the ground where somehow overpainted with white color used for the walls.

So you are right the ground is the problem.

I also checked if putting a sticker over the ground of the german plug adapter at another wall socket works and it was fine. Is it a problem when the computer works without a ground?

So how this problem is solved for other notebooks? Is the power supply the problem? Something inside the computer?

Thanks for the tip.

spowi

 

Turn off electricity supply to your house. Scrape off the white paint for the ground contact pins to be able to contact the AC plug pins.

 

I prefer using ungrounded power supplies because the mains cables are thinner and lighter (and some places where I work there isn't a functioning ground system for the power sockets). With some computers it is possilbe to get slight electrical shock when touching metallic parts if there is no ground system. However, this is not dangerous because it is some leakage through a high resistance circuit. I actuallyu got a couple of these adaptors so I can use the lighter ungrounded mains cables with PSUs which have 3 pin connectors. I also avoid the problem you have encountered.

John

 

OK, thanks John.

Maybe at last some comments in general to the notebook after one month of using it:

i like:
* screen
* keyboard touch + led light
* trackpad after turning off different options
* size+weight
* and most important battery runtime up to 6 hours working with matlab

i don't like:
* usb only at left side (right is better for wired mouse)
* keyboard hits the monitor when notebook is closed ... now i have a thin soft layer to protect in between
* mini vga ground problem mentioned above
* worse WLan reception

spowi

 

Good point - it happens with the NP700Z5 too, leaving smudges on the display.