Micro A1 graphics question

I hope this is the correct forum for this. I am having a problem with my Micro A1. I am running OS4 update 2. (although this has been an issue since plain 4.1, not sure about 4.0) I have an LCD panel monitor with a native resolution of 1366 x 768. I made a screenmode for this monitor with that width and height. However, the monitor reports that the computer is outputting 1280 x 768 regardless of what I do. Is there some imposed limit on the aspect ratio of what the graphics chip can render? It seems like 1366 x 768 is a rather common resolution. Has anyone else had this issue? Advice?

Thanks in advance.

@graffias79

Try to enable DDC in Prefs/ScreenMode and check what happens.

@graffias79

Note that DDC might not work if your monitor has a VGA connector and you use a VGA-DVI adaptor to connect to the micro. Those adaptors often don't connect the DDC conductors through from one side to the other.

@graffias79

Just a guess, but the monitor is probably determining the resolution by looking at the hsync and vsync frequencies retlative to standard VESA hsync and vsync frequencies. Have you compared your freqs to the standard VESA ones?

The monitor that I have has a standard VGA port, so there are no DVI connectors or adapters involved. The monitor is a Dell IN1910N. I also tried with my Acer AL2017, which has a native resolution of 1400x1050. (that the A1 has no problem acheiving) Both of these monitors report the horizontal resolution as 1280.

I just tried DDC mode and it works. It is strange that I couldn't define it manually. Oh well I am glad that it worked!

Thanks for you help!