Asus vg278h 3D enabled with ATI lightning 7970 ?

As far as I know, you need an Nvidia card to run 3D on that monitor, so no. However, I'm not an expert on 3D so I could be wrong.

You will have to install and use 3rd party software to play with AMD's HD3D.

Also, I think you'll need a mini-DP to DL-DVI adapter (which cost I think around $100) to run 120 Hz on the Lightning since that monitor doesn't have a DisplayPort input.

Again, could be wrong on that, but I don't think the SL-DVI on the card can run 120 Hz.

can you give me some more info about "3rd party software"?

@BigMack70
I don't think I need any extra adapters. Can someone confirm this ?

Well I'm 99.9999999999% sure you can't run 120 Hz 1080p on single-link DVI (both the Lightning's DVI outputs are single link).

The only thing I'm NOT sure about is if you can run 120 Hz over the mini DP --> HDMI adapter that is included. I don't think you can, but don't know enough to say for sure.

for 3D with glasses I ll run 60 FPS and 60HZ, and 120 HZ without 3D

It needs to be 120 Hz for 3D. No exceptions.

I guess I have to buy GTX680 ? ;( or it's same?

Here's some research material:
http://www.tomshardware.com/reviews/geforce-3d-vision-h...

Unfortunately the 7970 Lightning is just not built for anything other than 1080p 60 Hz unless you have a DisplayPort monitor, and I think the only 27" 120 Hz 3D monitor with DiaplayPort currently is this one which just looks ugly to me:
http://www.newegg.com/Product/Product.aspx?Item=N82E168...