drivers - Unable to use nvidia gpu with optimus on ubuntu 16.04

I'm having a dell inspiron 7567 in which im not able to use the nvidia gpu (Geforce GTX 1050). At first i only installed the nvidia driver and tried signing the MOK by following the steps from
https://gist.github.com/Garoe/74a0040f50ae7987885a0bebe5eda1aa
since i'm using UEFI and enabled secure boot.

When i used the command glxinfo|egrep "OpenGL vendor|OpenGL renderer"
i found that my laptop was still using the intel gpu even when gazebosim was running.

Then decided to use bumblebee and did all the steps as mentioned in this video. After doing everything in the video i restarted my laptop and i found the indicator as the guy from the video got( it shows me the nvidia logo instead of the intel logo that the guy from the video got ) but was still not able to change to the nvidia gpu with it.

When i tried running optirun glxgears i get the following error

[ 3411.396308] [ERROR]Cannot access secondary GPU - error: Could not load GPU driver

[ 3411.396337] [ERROR]Aborting because fallback start is disabled.

for lspci -vnn | grep '\''[030[02]\]' i get

00:02.0 VGA compatible controller [0300]: Intel Corporation Device [8086:591b] (rev 04) (prog-if 00 [VGA controller])

01:00.0 VGA compatible controller [0300]: NVIDIA Corporation Device [10de:1c8d] (rev a1) (prog-if 00 [VGA controller])

for sudo inxi -G i get

Graphics: Card-1: Intel Device 591b
Card-2: NVIDIA Device 1c8d
Display Server: X.org 1.18.4 drivers: (unloaded: fbdev,vesa)
tty size: 80x24 Advanced Data: N/A for root

in my bumblebee.conf file i changed Driver= to Driver=nvidia, Bridge=auto to Bridge=primus,replaced nvidia-current with nvidia-378(which is the nvidia driver im using), changed PMMethod=auto to PMMethod=bbswitch the rest of the file is left as default

for sudo lshw -numeric -C display i get

*-display UNCLAIMED
description: VGA compatible controller
product: NVIDIA Corporation [10DE:1C8D]
vendor: NVIDIA Corporation [10DE]
physical id: 0
bus info: pci@0000:01:00.0
version: a1
width: 64 bits
clock: 33MHz
capabilities: pm msi pciexpress vga_controller bus_master cap_list
configuration: latency=0
resources: memory:d2000000-d2ffffff memory:c0000000-cfffffff memory:d0000000-d1ffffff ioport:e000(size=128) memory:d3000000-d307ffff
*-display
description: VGA compatible controller
product: Intel Corporation [8086:591B]
vendor: Intel Corporation [8086]
physical id: 2
bus info: pci@0000:00:02.0
version: 04
width: 64 bits
clock: 33MHz
capabilities: pciexpress msi pm vga_controller bus_master cap_list rom
configuration: driver=i915 latency=0
resources: irq:126 memory:d4000000-d4ffffff memory:b0000000-bfffffff ioport:f000(size=64) memory:c0000-dffff

my nvidia x server settings dont have many tabs. It only shows me application profiles tab and nvidia settings configuration when its supposed to have many more tabs.

i read a lot about this issue on different forums but i still could'nt get it to work. So could somebody please give me a fix for this. Thanks in advance.