Argthtjtr

Got this odd problem where the image in the monitor is offset to the right. It’s offset a lot.

I have an external monitor, which is connected to a laptop. I don’t use the laptop’s display, only the external monitor. The monitor is Asus AL2216W (found a manual). It’s connected through VGA. The video card is Mobile Intel 965 Express Chipset.

Today, I needed to connect the monitor to another laptop. It worked. When I’ve connected the monitor back to my main laptop, the image in the monitor is offset.

Here's what I've tried so far:

1. My monitor has a button for auto adjustment. I didn’t remove the offset


2. My monitor has a menu for manual adjustment for the horizontal position. But, the offset is so large that this adjustment doesn’t have enough range.


3. I have unplugged and powered down the monitor. The offset is still there.


4. If I change the resolution to 1600 by 1200, the image becomes properly centered, and there is no offset. But, when I change it back to 1680 by 1050, the offset is back.


5. Connected the monitor to yet another laptop. The offset is still there; same amount of offset. That implies that the problem is in the monitor, and not in the video card.

Are there more things I could try?

update: I've bought another monitor with 1680 by 1050 resolution. It's a different model, although I don't know if that matters. It worked right away. The mystery of the offset will, probably, remain unsolved.

I had a similar Problem and it helped to change the refresh rate with the corresponding resolution.

For Example, I was able to choose between

• 1920x1080:60Hz


• 1920x1080:59Hz


• 1920x1080:58Hz

With 60Hz I had a split and an offset in my screen but with 59Hz everything worked fine.

Sounds like you solved the problem yourself. This is NOT an issue with the actual monitor.

Set the resolution to 1600x1200. That's most likely either the native resolution of the monitor OR the best that your laptop can do without jacking the image. Either way that's what appears to work.

It sounds like the offsets for the video card and external monitor don't match up; barring simplistic software issues (the driver got part of the offset wrong), the basic issue is probably that the video card is sending out the VGA signal in a way that the monitor is interpreting incorrectly.

Part of the answer to this question lies in how pixel data is transmitted over VGA: If you could look at the data coming over the cable, it would basically look like a line-by-line scan of each frame coming in; this protocol was designed for CRT monitors, where each pixel on the screen is basically hit in sequence, based on the signal coming in.

• Between the rows of actual pixel data, there's a few rows of "blank" pixels between each frame, which allow time for the CRT beam to travel from the bottom right corner back to the upper left (since the protocol was designed for CRT monitors)


• There's also a few "blank" pixels past the end of the scan line that allow time for the beam to travel to the start of the next scan line.

So imagine getting a long sequence of pixels over the wire; if you guess the height/width of the signal wrong, it'll look wrong. If the front porch/back porch of the signal is out of spec, this kind of offset can occur. (See this diagram for more details.)

I resolved it by reducing the colour depth to 16bit. Guess too much information is sent across with 32bit and the slow VGA standard/cable/whatever isn't coping