I’ve added a 22 inch 2nd monitor via thunderbolt to DVi cable to my 27 in iMac. I have the resolution set to 1680 x 1050 on the Acer X223W 22 in monitor ( no option for higher available ) and I have the 27 in iMac set to 256 x 1440.

As you can see in the photo the e channel is massive. I used to use this 22 inch monitor with my pc and had much finer resolutions.

Is there any way to get a better resolution on this X223w Acer monitor?

I’m giving up after a day and a half of net research. It must be a restriction of the Radion 6700 graphics card on my iMac. I was able to get a much higher resolution with this X223W acer monitor connected to my pc. Grrrr

The connector you’re using is DVI single link. The maximum resolution at 60Hz for single link DVI is 1,920 × 1,200.
I don’t know what resolution you want, but if you want higher than 1920x1200 you’ll need a different cable.

Yea you will most likely need a new cable that can handle higher resolutions. You can look and see if FireFold has the cable you need. That’s where I normally get all my cables at.

The native resolution of that monitor is only 1680x1050.

Unless you have a much higher resolution monitor than the resolution you are using, native is going to give the most superior (crisp) viewing.