U2711 DVI-D2 doesn't work

Hi,

I have just purchased a Dell U2711 screen to use with my digital TV set-top box (STB) and my PC at the same time. My STB has an HDMI out with HDCP and Dell confirmed me in chat that this would work fine with an HDMI-to-DVI-D cable (because the U2711 HDMI in doesn't support HDCP). It does, on the DVI-D1 in connector. My PC has a video card that supports up to 2560x1440 over DVI-D, which works fine on the DVI-D1 connector as well.

But no matter which I connect to DVI-D2, I don't get a signal. The STB gives noise on this input. The PC refuses to recognise there is a monitor connected.

I tried playing with my PC settings, setting the screen to a much lower resolution and connecting both, etc. Nothing works: DVI-D2 doesn't work.

Any hints on how to connect these two devices to the screen ?

Thanks,

Peter.