G73Jh AC power interferes with d-sub output?

Okay, this is more of a "for future reference" question than anything since I'm upgrading my monitor to one with HDMI capability soon.

But basically, the issue is that when outputting to my 22" Samsung LCD via the d-sub VGA port on the G73Jh, I get some kind of electrical interference from the AC adapter. It causes minor "waves" to appear in my monitor's display, and if I unplug the AC adapter the interference (and thus the "wave" issue) immediately stops and the image quality returns to its expected flawlessness.

And allow me to specify, when I say the issue is minor, I mean that half the time I don't even notice unless I'm really looking for it or I'm looking at an especially dark portion of the screen (it's fairly noticeable when watching a 4:3 pillarboxed video, for example). Like I said, this isn't a huge deal because I'm getting a new HDMI-capable monitor soon anyway. But I'd love to know if anyone else has noticed this and if there's any means of fixing it (perhaps using something rubber to put a bit of extra insulation between the wires or something?)

Additionally, it is definitely a problem specific to the d-sub port (which is why I suspect that it's electrical interference, the port is directly adjacent to the AC adapter port). When outputting via HDMI to my 40" Samsung LCD HDTV, I have no issues of this kind (or any issues at all, it's beautiful on the HDTV). Likewise, when using this monitor via d-sub or DVI with any other computer, there is no issue of which to speak.

Anyone else seen this? Is there anything I can do about it?

 

Do you have dirty power? Have you tried using a power conditioner (not just a surge protector)?

Does this happen with the battery out on AC power as well?

 

No I don't have dirty power, and I don't have access to a power conditioner.

This does continue happening with the battery removed. The only thing I've found that corrects the issue is simply unplugging the AC adapter and running from battery power.

I also have no issues of any kind with other devices plugged into this surge protector or outlet, which is another reason I believe it to be a matter of interference. For the sake of being thorough, I tried a separate surge protector and outlet before posting this, and the problem persisted.

 

Is it set to the correct refresh rate? Have you tried a different monitor with the VGA output?

Have you tried ground-lifting the monitor (warning: not a great idea for CRTs)?

 

Yes to both the refresh rate and different monitor. No to the ground-lift, and I'm not going to (but as stated, it's an LCD).

I really am 99% certain that it's an issue with simple interference between the AC adapter's current and the d-sub port.

Has anyone who actually owns a G73Jh either seen or figured out this issue?

 

I never had that issue with my G73Jh, I think your best bet is to try another monitor and see if you can reproduce it, unless someone else here has seen this (I haven't seen it mentioned ever).

You could also try a different version of your graphics driver, or maybe a different VBIOS if you're comfortable with that.

 

You have a grounding loop being created between the Samsung and the laptop, and the power brick. You can test this by connecting either the laptop or LCD to another circuit in the house.

This is happening because your ground isn't properly grounded, and you are getting frequency feedback over your AC power. I bet if you put a tester on your AC plugs, you would get a wiring fault indicator. You could also try plugging the the components into a UPS and see if the UPS isolates the situation.

 

I am also experiencing something like this, In my case it's the speakers. Every time I plug in my AC adapter, I will start hearing low frequency sounds in my logitech 2.1 speakers. It's not that loud or anything, It's just annoying sometimes.

 

You're definitely onto something with this Chastity.

First off, the house I live in is well over 100 years old, and we don't actually have any properly grounded outlets in the entire house (I know, that's bad).

Unfortunately, I can't quite manage to fully test this without moving my entire setup to another room, because this whole room is on one circuit. However, plugging the laptop into a surge protector on the far side of the room while leaving the monitor plugged into its original location did significantly decrease the appearance "waves."

I don't suppose you can recommend a full solution to this issue that wouldn't involve me:
- relocating my entire desk,
- buying something expensive, or
- hiring someone to ground my outlets?

I'm no electrician, but I'm guessing that it's not a simple enough issue that it can be fixed without doing one of those three things. But if you happen to have such a solution I'd be very grateful.

 

Expensive is a relative term. Buying a small UPS might help. They typically have very good power conditioning circuits in them and it will seperate the ground loop in the circuit from the laptop. The one I have was about $100 but you can buy smaller ones cheaper. In this case I don't think the size of the ups matters as long as it is a good name brand like APC.

I have this one and it is $87.
This one is only $50 and would probably do the job.

I can't swear that this will solve your problem but I am pretty sure it will. It is never a bad idea to have good surge protection and line conditioning on the items in your computer room. Especially when you have questionable circuitry. My 62 inch Toshiba DLP television blew it's $400 lamp within three months of purchase. They replaced it under warranty. I put the TV on the APC ups linked above. The next bulb lasted over four years. I just replaced it a few weeks ago. This is because the TV didn't suffer any power surges or brown outs due to having the battery backup and line conditioning.

 

A simple test is to utilize a 50' extension cord feeding off another circuit in the house. As for the house grounding, it really isn't all that hard to improve. You are probably using an earth-based neutral. Your local utility probably now has a system-neutral running with their power lines. (2 AC lines for 2 phases, plus a system neutral for 3 wires total) An electrician could swap out the old earth-ground with a connection to the system ground.