gnome 3.4 fallback mode

[enginco]

hi,

my computer configuration is:

linuxmint:
Release 1 (debian) 64-bit
Kernel Linux 3.2.0-3-amd64
GNOME 3.4.2

my problem is:
yesterday my gnome is upgraded. Now desktop graphics are very bad.
I googled but I couldn't solve this problem.

Before, my GLX Renderer wasn't "Gallium 0.4 on NV86"

inxi -Gxc 0

Code: Select all

Graphics:  Card NVIDIA G86 [GeForce 8400M GT] X.Org 1.12.1.902 Res: 1280x800@59.9hz 
                GLX Renderer Gallium 0.4 on NV86 GLX Version 2.1 Mesa 8.0.3 Direct Rendering Yes

How can I solve it?
thanx...

[enginco]

hi,
I installed nvidia drivers by synaptic package manager.
And there are no changes.

Now, I have a new big problem
It disabled my brightness keys functions.
It burns my eyes...