External monitor changes resolution after sleep

[snowwing]

My external monitor resolution is set to 1680X1050 and my macbook pro display is black. If i leave the MCP in clamshell mode and it goes to sleep, when I move the mouse to wake it, he external monitor resolution is much lower (1280X800). I have to close the MBP then "wake" it to get back to 1680X1050.

In System Preferences the monitors are mirrored.

It's not a big deal for me but I'm about to move my wife from the Darkside to a MCB. Is there a simple fix for this.
Thanks
Ron

 

[cameronwilby]

It sounds like the monitor itself causing the issue than the laptop.

I'm taking a stab at this explanation because I don't know what monitor, what connection etc, but I'm guessing it's this.

When a monitor is connected to the MBP using a DVI cable, the monitor will usually tell the laptop what it's optimal resolution is. In this case, the MBP is not getting this signal and so setting the resolution at a rather bog standard 1280x800.

Have you tried connecting your laptop to another monitor?

 

[snowwing]

It's a Viewsonic monitor about three years old. I had it with my Windows machine. I don't have another to try your suggestion.
Thanks
Ron