lspci
00:00.0 Host bridge: Intel Corporation Xeon E3-1200 v3/4th Gen Core Processor DRAM Controller (rev 06)
00:01.0 PCI bridge: Intel Corporation Xeon E3-1200 v3/4th Gen Core Processor PCI Express x16 Controller (rev 06)
00:02.0 VGA compatible controller: Intel Corporation 4th Gen Core Processor Integrated Graphics Controller (rev 06)
00:03.0 Audio device: Intel Corporation Xeon E3-1200 v3/4th Gen Core Processor HD Audio Controller (rev 06)
00:14.0 USB controller: Intel Corporation 8 Series/C220 Series Chipset Family USB xHCI (rev 05)
00:16.0 Communication controller: Intel Corporation 8 Series/C220 Series Chipset Family MEI Controller #1 (rev 04)
00:1a.0 USB controller: Intel Corporation 8 Series/C220 Series Chipset Family USB EHCI #2 (rev 05)
00:1b.0 Audio device: Intel Corporation 8 Series/C220 Series Chipset High Definition Audio Controller (rev 05)
00:1c.0 PCI bridge: Intel Corporation 8 Series/C220 Series Chipset Family PCI Express Root Port #1 (rev d5)
00:1c.3 PCI bridge: Intel Corporation 8 Series/C220 Series Chipset Family PCI Express Root Port #4 (rev d5)
00:1c.4 PCI bridge: Intel Corporation 8 Series/C220 Series Chipset Family PCI Express Root Port #5 (rev d5)
00:1c.5 PCI bridge: Intel Corporation 8 Series/C220 Series Chipset Family PCI Express Root Port #6 (rev d5)
00:1d.0 USB controller: Intel Corporation 8 Series/C220 Series Chipset Family USB EHCI #1 (rev 05)
00:1f.0 ISA bridge: Intel Corporation HM86 Express LPC Controller (rev 05)
00:1f.2 SATA controller: Intel Corporation 8 Series/C220 Series Chipset Family 6-port SATA Controller 1 [AHCI mode] (rev 05)
00:1f.3 SMBus: Intel Corporation 8 Series/C220 Series Chipset Family SMBus Controller (rev 05)
01:00.0 3D controller: NVIDIA Corporation GM107M [GeForce GTX 850M] (rev a2)
03:00.0 Ethernet controller: Qualcomm Atheros Killer E2200 Gigabit Ethernet Controller (rev 13)
04:00.0 Unassigned class [ff00]: Realtek Semiconductor Co., Ltd. Device 5249 (rev 01)
05:00.0 Network controller: Intel Corporation Wireless 3160 (rev 83)

Alt+control+F1
-sudo service gdm stop
unrecognized service
-sudo service lightdm stop
unrecognized service
-sudo service mdm stop
mdm stop/waiting
 se puede instalar ya 
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Would you like to register the kernel module sources with DKMS? this will allow DKMS to automatically build a new modulem If you install a diferent kernel later. Yes   NO
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Al elegir Yes me da errores.

Error: failed to run `/usr/sbin/dkms build -m nvidia -v 343.22 -k 3.13.0-24-generic:
Kernel preparation unnecesary for this kernel. Skipping...
Building module:
cleaning build area....
make KERNELRELEASE=3.13.0-24-generic module
KERNEL_UNAME=3.13.0-24-generic;make -C uvmmodule
KERNEL_UNAME=3.13.0-24-generic
KBUILD_EXTMOD=/var/lib/dkms/nvidia/343.22/build/uvm....(bad exit status:2)
Error! Bad return status for module build on kernel:
3.13.0-24-generic (x86_64)
Consult /var/lib/dkms/nvidia/343.22/build/make.log for more information.
ok

Error: Failed to install the kernel module through DKMS. No kernel module was installed; please try installing again without DKMS, or check th DKMS logs for more information.

ok

Error: Installation has failled. Please see the file '/var/log/nvidia-installer.log for details. You may find suggestions on fixing installation problems in the README available on the linux driver download page at www.nvidia.com

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He vuelto a empezar pero sin  poner kernel y otro error:

Error youdo not appear to have libc header files installed on your system. please install your distribution's libc development package

lo he solucionado con:

sudo apt-get install libc6-dev.

se ha instalado correctamente