T430 external display problem

[AKUK]

I am having a problem with my brand new T430.

I have purchased a miniDP to HDMI adapter, if I connect the adapter to my thinkpad and then an HDMI cable from the adapter to the external monitor it will correctly duplicate the display. However when I use the Fn to switch between duplicate, extend etc. I cannot get it back to successfully duplicate. If I disconnect the adapter and reconnect it will not then duplicate the display.

If I enter the monitor properties on Windows 7 the internal display is labelled as display 1 and 2 whereas the external display is labelled as display 3.

Anyone else experienced this?

This is my spec:

i7-3520M (3.6GHz)
8GB Corsair Vengence RAM
250GB Samsung 840 SSD
14in 1600x900 HD+ LCD
NVIDIA NVS 5400M 2GB
Win7 Pro 64

Thanks

[AKUK]

I called Lenovo and they helped me resolve the issue.

It is a known bug with the HD4000/Nvidia switchable graphics, Windows is not able to control the clone display so in order to clone the display you must open Nvidia control panel, goto setup multiple displays, if the internal monitor shows as 'Laptop Display' and 'Analogue Display' then untick Analogue display. Make sure the external display is ticked, right click the Laptop Display and select Clone and clone to the external. Then click Apply at the bottom of the screen.