Monitor tearing when AC adapter plugged in...help!

I'm on an ASUS Z71v which has a GeForce Go 6600.

I just hooked up a new Acer AL2216W and am experiencing a very strange issue. When the laptop is plugged in, there is "tearing" on the screen....minor tearing but noticeable! When I unplug the laptop from the power, the tearing goes away!

Anyone have any idea of what this could be and how to fix it?

Thanks!

 

Does your laptop have a 3 pin connector to the power supply? The cause is probably a hum loop where some stray current is going round an earth loop because both the computer and monitor are earthed (grounded) and there is an earth connection between them.

This used to be a regular problem in the says when audio equipment and would cause a "hum". Hence the term hum loop.

Somehow you need to break the earth loop. It may be enough to connect the computer and monitor to different power sockets. Otherwise you have to break the loop somewhere by disconnecting an earth wire to either the computer or the monitor, but first try a different cable between the two (unless it is fixed to the monitor). There is also the possibility that the monitor cable is picking up noise.

John

PS: See this thread.

 

thanks so much for the quick response...this makes sense. i've connected the laptop to a different power supply and haven't seen the problem again.

many thanks!