filipe@asgard:~$ dpkg -l | grep -i "ii  nvi"
ii  nvidia-304                                                  304.117-0ubuntu1                      amd64        NVIDIA legacy binary driver - version 304.117
ii  nvidia-libopencl1-304                                       304.117-0ubuntu1                      amd64        NVIDIA OpenCL Driver and ICD Loader library
ii  nvidia-opencl-icd-304                                       304.117-0ubuntu1                      amd64        NVIDIA OpenCL ICD
ii  nvidia-prime                                                0.6.2                                 amd64        Tools to enable NVIDIA's Prime
ii  nvidia-settings                                             331.20-0ubuntu8                       amd64        Tool for configuring the NVIDIA graphics driver

filipe@asgard:~$ sudo lspci -vnn | grep VGA -A 15
00:02.0 VGA compatible controller [0300]: Intel Corporation 3rd Gen Core processor Graphics Controller [8086:0166] (rev 09) (prog-if 00 [VGA controller])
        Subsystem: Sony Corporation Device [104d:909c]
        Flags: bus master, fast devsel, latency 0, IRQ 45
        Memory at b9000000 (64-bit, non-prefetchable) [size=4M]
        Memory at c0000000 (64-bit, prefetchable) [size=256M]
        I/O ports at 7000 [size=64]
        Expansion ROM at <unassigned> [disabled]
        Capabilities: [90] MSI: Enable+ Count=1/1 Maskable- 64bit-
        Capabilities: [d0] Power Management version 2
        Capabilities: [a4] PCI Advanced Features
        Kernel driver in use: i915

00:14.0 USB controller [0c03]: Intel Corporation 7 Series/C210 Series Chipset Family USB xHCI Host Controller [8086:1e31] (rev 04) (prog-if 30 [XHCI])
        Subsystem: Sony Corporation Device [104d:909b]
        Flags: bus master, medium devsel, latency 0, IRQ 41
        Memory at b9400000 (64-bit, non-prefetchable) [size=64K]
--
01:00.0 VGA compatible controller [0300]: NVIDIA Corporation GK107M [GeForce GT 640M LE] [10de:0fd3] (rev a1) (prog-if 00 [VGA controller])
        Subsystem: Sony Corporation Device [104d:909c]
        Flags: bus master, fast devsel, latency 0, IRQ 16
        Memory at b8000000 (32-bit, non-prefetchable) [size=16M]
        Memory at a0000000 (64-bit, prefetchable) [size=256M]
        Memory at b0000000 (64-bit, prefetchable) [size=32M]
        I/O ports at 6000 [size=128]
        Expansion ROM at <ignored> [disabled]
        Capabilities: [60] Power Management version 3
        Capabilities: [68] MSI: Enable- Count=1/1 Maskable- 64bit+
        Capabilities: [78] Express Endpoint, MSI 00
        Capabilities: [b4] Vendor Specific Information: Len=14 <?>
        Capabilities: [100] Virtual Channel
        Capabilities: [128] Power Budgeting <?>
        Capabilities: [600] Vendor Specific Information: ID=0001 Rev=1 Len=024 <?>
        Kernel driver in use: nvidia
filipe@asgard:~$ lsmod | egrep "nvidia|i915"
nvidia              11334886  0 
i915                  783805  2 
i2c_algo_bit           13413  1 i915
drm_kms_helper         53081  1 i915
drm                   303102  3 i915,drm_kms_helper
video                  19476  1 i915
filipe@asgard:~$ glxspheres64 
Polygons in scene: 62464
Xlib:  extension "GLX" missing on display ":0".
ERROR (603): Could not obtain RGB visual with requested properties
grep -i glx /var/log/Xorg.0.log
[    40.149] (II) "glx" will be loaded by default.
[    40.149] (II) LoadModule: "glx"
[    40.149] (II) Loading /usr/lib/x86_64-linux-gnu/xorg/extra-modules/libglx.so
[    42.870] (II) Module glx: vendor="NVIDIA Corporation"
[    42.870] (II) NVIDIA GLX Module  304.117  Tue Nov 26 21:45:09 PST 2013
[    42.870] Loading extension GLX
[    43.573] (EE) Failed to initialize GLX extension (Compatible NVIDIA X driver not found)
filipe@asgard:~$ grep -i glx /var/log/kdm.log
Loading extension GLX
Loading extension GLX
filipe@asgard:~$ grep -i nvidia /etc/modprobe.d/*
/etc/modprobe.d/blacklist-framebuffer.conf:blacklist nvidiafb
/etc/modprobe.d/fbdev-blacklist.conf:blacklist nvidiafb
/etc/modprobe.d/nvidia-304_hybrid.conf:# This file was installed by nvidia-304
/etc/modprobe.d/nvidia-graphics-drivers.conf:# This file was installed by nvidia-304
/etc/modprobe.d/nvidia-graphics-drivers.conf:blacklist nvidia-173
/etc/modprobe.d/nvidia-graphics-drivers.conf:blacklist nvidia-96
/etc/modprobe.d/nvidia-graphics-drivers.conf:blacklist nvidia-current-updates
/etc/modprobe.d/nvidia-graphics-drivers.conf:blacklist nvidia-173-updates
/etc/modprobe.d/nvidia-graphics-drivers.conf:blacklist nvidia-96-updates
/etc/modprobe.d/nvidia-graphics-drivers.conf:alias nvidia nvidia_304