Posted this in the graphics section but I think it's probably most relevant in this section.
I have a Dell Studio XPS 1640 with the ATI Radeon Mobility 4670 graphics card. Up next to the F12 key there is a key specifically for switching between displays. It worked fine with Vista, now with Win 7 it doesn't switch. Here is a breakdown of exactly what happens:
Laptop on alone, push the button and an on screen display window pops up saying "No external monitor detected"
Connect to my TV through HDMI- automatically the TV is used as a duplicate display and audio goes through the HDMI to the TV. Push the button to switch and the on screen display has: LCD LCD+HDMI HDMI to choose between. However toggling between them does not cause the monitors to switch.
I can use the win key +P to make them switch and that works properly, but then I do not get audio through my HDMI.
The aforementioned display key works properly from the BIOS.
In addition, the on screen display when using the display switch key seems to have everything backward if I have changed it through the win +P command. When only on laptop lcd the OSD says it's on LCD+HDMI. When on duplicate (both lcd and HDMI on) the OSD shows it on HDMI only, and when only the HDMI is used the OSD shows LCD only.
Looks like it must be a Win 7 issue, I'm wondering if there is a fix. The biggest problem is that I use my laptop to play blu ray movies on my HDTV and it won't play them with both displays on due to the copyright protection, and if I use the win +p command to use just HDMI, I don't get any audio. Any help is appreciated.
are you sure that the drivers from the laptop mfg for the key switching are supported in 7, if they are, get ahold of their tech support and ask what gives, and as a thought, copy protection could be the cause