External Monitor doesn't fill during logn with HDMI connection

I’ve had this trouble ever since having a HDMI external monitor on my notebooks with Linux Mint. The logon screen is always shifted to the left of the external & the logo not centered. Doesn’t matter which notebook I’ve used, one a Toshiba Satellite A665-S6086 with Intel HD Graphics only, or an MSI FX603 with Intel HD Graphics & nVidia Geforce GT425M.

What is the cure for this? Have never been able to find a solution through Google, the Mint forum, or anywhere.

Notebook screens both are 1366x768 & external(s) 1920x1080.

Thanks for any solution to point me in the right direction.

I have had similar trouble using different HDMI monitors. I have had good results using xrandr from the command line paying attention to setting the correct resolution values for HDMI.

Here is a link that does a good job explaining how to do this.

Perhaps you could write a bash script and insert it into ~/.kde/Autostart so it would execute upon login.