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I have two monitors in my machine. One is an old LCS samsung monitor. Recently, I started to hear a small hum in my speakers (subwoofer) and replaced them. The new one also got the issues then I found our that its a grounding issue. I unplugged the PC's power chord. The monitor is still switched on. When I checked, there's current in the earth pin (ground pin). When I unplug the monitor, there's no current and the speaker is normal. Now, I have moved that monitor to my dad's machine and took his monitor.

My question is, is it a big issues? The house's earthing system is working and its grounding the current. I won't feel it if I touch the machine like in many other cases.

  • But still, is it good to keep that monitor attached to my machine?

  • Can it harm the computer?

  • What should I do?

share|improve this question
@Breakthrough That question is related to the charger of a laptop. This is a desktop and related to a monitor. In that case and most of the others the house have a grounding problem. But in my case, the house have a good grounding system and the current flows through it without giving a shock to anyone who touch the equipment. I asked, even if there is a good earthing system, since a stray current is flawing through the VGA port and going out through the ground of the PC, can it still damage my machine? – THpubs Jun 28 '13 at 3:10
I'm assuming you mean LCD and not LCS - does the monitor have a separate power supply or is it built into the LCD. Do you see any sparks when plugging in the VGA cable? – Journeyman Geek Jun 28 '13 at 3:48
A stray current is never safe. – Xavierjazz Jun 28 '13 at 6:20
up vote 1 down vote accepted

The most likely issue is that one of the transformers in the monitor has bad insulation and is leaking voltage through to the grounding. I would guess the breakdown of the insulation will get worse, not better and more voltage/current will leak. Depending on what the voltages are, it could get dangerous.

Theoretically, since the voltage is being drained by the ground, it is changing the reference to ground so from the computer's point of view is that it appears as through you are experiencing a voltage drop. (The incoming voltage isn't referencing itself to zero ground, but a higher than zero ground) This could overheat the system and damage it. Hard to say exactly what will happen - depends on voltage leaking, whether it gets worse... Regardless, you know you have a voltage leak. Sad to say, safer to replace.

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Is it possible to repair it? – THpubs Jun 28 '13 at 3:39
If it is one of the transformers, the theoretical answer is yes, the realistic one is no. – Blackbeagle Jun 28 '13 at 6:53

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