Laptop delivers blurry image to external monitors

Question

I have 3 laptops in my hand at the moment. One Old Toshiba, a DELL and a Sony Vaio. The only one that delivers a crisp image to my external monitor is the Dell. Both others have blurry, bad quality image. I wonder if anyone else is experiencing the same issue, and if and how it can be fixed.

The connection is done via VGA cable.

Resolution is set to the appropriate supporting one for the external monitor (1680 * 1050). I tried at 60 and 75 hz (these are the only options I get available)

All drivers are updated to the latest available.

* UPDATE * Just to answer the question. I haven't found out the reason, but it sure is not the cable. I have bought a new laptop since (I insisted on looking at the external monitor signal quality before buying it) and it seems that some laptops just have a bad signal, for whatever reason. So my suggestion to all, plug an external monitor to the laptop before buying it, or at least make sure you are allowed to change / give back the laptop if it does not offer a good signal.

Solution 1

Couple of possibilities:

1. VGA cable is of poor quality. Find a good quality (usually THICKER) cable with ferrite cores. It could also be that you are running the cable too close to power wires - power wires will cause interference, especially over long distances, with both VGA and network cables.

2. Laptop(s) may internally have poor quality electromagnetic shielding or are just plain bad. I've seen this many times in multiple laptops. Usually the DAC's (Digital to Analog Converters) are to blame, other times it is the cramped spacing of components inside the laptop causes interferences that manufactures "let slip" for whatever reason.

Solution 2

I find that using the "Auto adjust" option on the external monitor helps a lot.

It bounces around a bit trying to optimize the image display, and it works well in most cases.

Solution 3

This can be caused from interference from the power supply. Unplug the AC adapter to see if this is the case. If so, replace it with a good quality aftermarket AC adapter.

Comments

[Spiros]

Oh, just in case anyone wonders, all drivers are updated to the latest available.

[Wayne Jhukie]

Same cable? This is almost certainly an analogue noise problem, which isn't easy to fix. I guess it's not possible to use DVI/HDMI?

[Spiros]

No unfortunately not. This monitor does not have DVI/HDMI input. Yes it's the same cable connected to the same monitor and 3 different laptops, so it has to be the laptops not the cable or the monitor (I guess).

[David Schwartz]

Find out what resolution and refresh rate the one that produces a good image is using and make sure to set the other one to those same settings. See if your video driver's utility has a "fine tuning" setting.

[Spiros]

Yep, seems like being so. Nothing you can do if it is the case.