How to start GNOME 3?

[KotletBanan]

I didn't find anything in search. Now, I'm on LiveCD, but I think, that after installation, I'll have the same problem. My Mint version is 12.

Instead of Gnome 3, I have a strange graphical environment that looks like Gnome 2 or Xfce. I guess that's MATE.
My question is: why I can't start a Gnome 3 session? On Fedora, Gnome 3 works fine :O

EDIT
Screenshot: http://i.imgur.com/EGxUG.png

[proxima_centauri]

Yes, that is GNOME3 fallback mode. You would get that desktop if your graphics card was not sufficient to run GNOME3, so there may be a problem detecting the graphics card or with the provided drivers.

Post your system specs please, specifically your graphics card.

[KotletBanan]

My graphic card is Gainward's Nvidia GTS450. I think, that should work.

There is my lshw's output: http://pastebin.com/TbDFD56E

[javajeff]

I think you are seeing Gnome 3 with all the extensions turned on. The Mint extensions make it look like a different DE, but it is Gnome 3. If you install Mint 12 and upgrade Gnome 3, there have been additional changes since Mint 12 came out.

http://www.gnome.org/gnome-3/