Ubuntu 15,04 & bumblebee

[ 4971.223037] [ERROR]Cannot access secondary GPU - error: Could not load GPU driver

[ 4971.223155] [ERROR]Aborting because fallback start is disabled.

[bumblebeed]
VirtualDisplay=:8
KeepUnusedXServer=false
ServerGroup=bumblebee
TurnCardOffAtExit=false
NoEcoModeOverride=false
Driver=nvidia
XorgConfDir=/etc/bumblebee/xorg.conf.d

[optirun]
Bridge=auto
VGLTransport=proxy
PrimusLibraryPath=/usr/lib/x86_64-linux-gnu/primus:/usr/lib/i386-linux-gnu/primus
AllowFallbackToIGC=false

[driver-nvidia]
KernelDriver=nvidia
PMMethod=auto
LibraryPath=/usr/lib/nvidia-current:/usr/lib32/nvidia-current
XorgModulePath=/usr/lib/nvidia-current/xorg,/usr/lib/xorg/modules
XorgConfFile=/etc/bumblebee/xorg.conf.nvidia

[driver-nouveau]
KernelDriver=nouveau
PMMethod=auto
XorgConfFile=/etc/bumblebee/xorg.conf.nouveau

[ 5195.660153] [DEBUG]Found card: 01:00.0 (discrete)
[ 5195.660185] [DEBUG]Found card: 00:02.0 (integrated)
[ 5195.660196] [DEBUG]Reading file: /etc/bumblebee/bumblebee.conf
[ 5195.660378] [INFO]Configured driver: nvidia
[ 5195.660397] [DEBUG]Skipping auto-detection, using configured driver 'nvidia'
[ 5195.660491] [DEBUG]Process /sbin/modprobe started, PID 28662.
[ 5195.660546] [DEBUG]Hiding stderr for execution of /sbin/modprobe
[ 5195.661686] [DEBUG]SIGCHILD received, but wait failed with No child processes
[ 5195.661866] [DEBUG]succesfully loaded bbswitch
[ 5195.661880] [INFO]Switching method 'bbswitch' is available and will be used.
[ 5195.661902] [DEBUG]Active configuration:
[ 5195.661911] [DEBUG] bumblebeed config file: /etc/bumblebee/bumblebee.conf
[ 5195.661921] [DEBUG] X display: :8
[ 5195.661930] [DEBUG] LD_LIBRARY_PATH: /usr/lib/nvidia-current:/usr/lib32/nvidia-current
[ 5195.661940] [DEBUG] Socket path: /var/run/bumblebee.socket
[ 5195.661949] [DEBUG] pidfile: /var/run/bumblebeed.pid
[ 5195.661959] [DEBUG] xorg.conf file: /etc/bumblebee/xorg.conf.nvidia
[ 5195.661968] [DEBUG] xorg.conf.d dir: /etc/bumblebee/xorg.conf.d
[ 5195.661977] [DEBUG] ModulePath: /usr/lib/nvidia-current/xorg,/usr/lib/xorg/modules
[ 5195.661987] [DEBUG] GID name: bumblebee
[ 5195.661996] [DEBUG] Power method: auto
[ 5195.662005] [DEBUG] Stop X on exit: 1
[ 5195.662014] [DEBUG] Driver: nvidia
[ 5195.662023] [DEBUG] Driver module: nvidia
[ 5195.662032] [DEBUG] Card shutdown state: 1
[ 5195.662134] [DEBUG]Process /sbin/modprobe started, PID 28663.
[ 5195.662184] [DEBUG]Hiding stderr for execution of /sbin/modprobe
[ 5195.663207] [DEBUG]SIGCHILD received, but wait failed with No child processes
[ 5195.663228] [DEBUG]Configuration test passed.
[ 5195.663254] [ERROR]Cannot open or write pidfile /var/run/bumblebeed.pid.

00:02.0 VGA compatible controller: Intel Corporation 2nd Generation Core Processor Family Integrated Graphics Controller (rev 09)
	Subsystem: ASUSTeK Computer Inc. Device 1642
	Kernel driver in use: i915
--
01:00.0 VGA compatible controller: NVIDIA Corporation GF108M [GeForce GT 540M] (rev a1)

Section "ServerLayout"
    Identifier  "Layout0"
    Option      "AutoAddDevices" "false"
    Option      "AutoAddGPU" "false"
EndSection

Section "Device"
    Identifier  "DiscreteNvidia"
    Driver      "nvidia"
    VendorName  "NVIDIA Corporation"

    BusID "PCI:01:00:0"

    Option "ProbeAllGpus" "false"

    Option "NoLogo" "true"
    Option "UseEDID" "false"
    Option "UseDisplayDevice" "none"
EndSection

ii  bumblebee-nvidia                      3.2.1-93~vividppa1                         amd64        NVIDIA Optimus support using the proprietary NVIDIA driver
ii  nvidia-304                            304.128-0ubuntu0.1                         amd64        NVIDIA legacy binary driver - version 304.128
ii  nvidia-current                        304.128-0ubuntu0.1                         amd64        Transitional package for nvidia-current
ii  nvidia-opencl-icd-304                 304.128-0ubuntu0.1                         amd64        NVIDIA OpenCL ICD
ii  nvidia-settings                       346.59-0ubuntu1                            amd64        Tool for configuring the NVIDIA graphics driver