macos - Can't display at full resolution on an external monitor from my MacBook

I have a 24" Asus V246H and a new MacBook ($999 one). I am trying to display to display to my Asus at 1080p via VGA. So I boot up with the lid closed and the external monitor plugged in. Everything boots up fine, but the resolution is really low. So I go in and change the resolution to be 1920x1080. My monitor then has a blue box on it that says "OUT OF RANGE". Lower resolutions like 1024x768 work, but 1680x1050 doesn't.

If I try mirroring my displays, the entire external monitor AND the entire laptop screen is completely garbled. I can make out some colors, but it is completely unusable.

I am suspecting that it simply won't work via VGA, but I don't want to buy another adapter, and my PC is using the DVI port.

Any solutions?

Answer

I had trouble getting my MacBook to output video to an external display as well. I had roughly the same thing happen with a DVI connection, so I don't think the VGA connection is what's causing the problem.

Try this:

1. Put the MacBook to sleep.


2. Plug the external display adapter (Mini DisplayPort to VGA) into the MacBook.


3. Insert a USB device into the MacBook (a mouse, a flash drive, whatever.)

The MacBook should wake up and output video to the external display at the native resolution of the external display. At least, that's what happens with mine.