HDMI output not working to my primary monitor

[yogisothoth]

I have Win7 ultimate, 2xNvidia 480GTX running in SLI and an ASUS VE278 monitor. It works fine using DVI but when I connect the monitor to the gc with the HDMI cable and switch the monitor to HDMI mode I get the Windows background, but no mouse pointer or anything to work with. If I try and boot the PC with just the HDMI cable attached the monitor says it can't find an input signal. Does anyone know what the problem here might be?

 

[CueBall1]

Now I have found out if I run dual monitor you can't use HDMI with S-vid or DVI at same time for some reason they fight Maybe this just something I have notice with vista and windows 7.

 

[yogisothoth]

I'm not even trying to run dual monitors - I'm just trying to run one primary monitor via HDMI

 

[Everlong]

Do you have the latest drivers and everything?

 

[yogisothoth]

Yes I have the latest Forceware drivers.

Cheers
Adam