Hi Leader bee. The forum is built to fuck with older threads. Doing so resurrects the thread. So your necro is most welcome.
Suggestions
- The main thing I would suggest is to consider the length of your cables. I've found that cables longer than 3m can result in the monitor not being detected.
- Are your drivers up to date 314.22?
- Rebooting.
- Bad cable?
Looking at
http://www.geforce.com/hardware/technol ... quirements and setting: "GeForce GTX 680"; "Single GPU"; "2D Surround"; "Landscape" ...
... the special instructions state "any connectors can be used to enable Surround". So although I haven't used HDMI there doesn't seem to be any reason why a HDMI should not work (it is, after all, there on your graphics card).
Perhaps the easiest thing to do is, as you've indicated, simply try a DVI to Display port cable (and/or buy a HDMI to Display port adapter).