Unable to switch to nvidia about optimus-manager HOT 7 CLOSED

▶ lspci -k | grep -A 3 NVIDIA
01:00.0 3D controller: NVIDIA Corporation GM108M [GeForce 940MX] (rev a2)
        Subsystem: ASUSTeK Computer Inc. GM108M [GeForce 940MX]
        Kernel driver in use: nouveau
        Kernel modules: nouveau, nvidia_drm, nvidia

▶ xrandr --listproviders
Providers: number : 2
Provider 0: id: 0x74 cap: 0xf, Source Output, Sink Output, Source Offload, Sink Offload crtcs: 3 outputs: 2 associated providers: 1 name:modesetting
Provider 1: id: 0x3f cap: 0x5, Source Output, Source Offload crtcs: 0 outputs: 0 associated providers: 1 name:modesetting

▶ cat /etc/X11/xorg.conf.d/10-optimus-manager.conf
Section "Device"
        Identifier "intel"
        Driver "modesetting"
        BusID "00:02:0"
        Option "DRI" "3"
        Option "modeset" "no"
EndSection

▶ inxi -Fxz                                       
System:    Host: PIPBOY Kernel: 4.20.17-1-MANJARO x86_64 bits: 64 compiler: gcc v: 8.2.1 Desktop: KDE Plasma 5.15.5 
           Distro: Manjaro Linux 
Machine:   Type: Laptop System: ASUSTeK product: X510UQ v: 1.0 serial: <filter> 
           Mobo: ASUSTeK model: X510UQ v: 1.0 serial: <filter> UEFI: American Megatrends v: X510UQ.309 date: 08/08/2018 
Battery:   ID-1: BAT0 charge: 30.5 Wh condition: 30.5/42.1 Wh (73%) model: ASUSTeK ASUS Battery status: Not charging 
CPU:       Topology: Dual Core model: Intel Core i7-7500U bits: 64 type: MT MCP arch: Kaby Lake rev: 9 L2 cache: 4096 KiB 
           flags: avx avx2 lm nx pae sse sse2 sse3 sse4_1 sse4_2 ssse3 vmx bogomips: 23240 
           Speed: 731 MHz min/max: 400/3500 MHz Core speeds (MHz): 1: 800 2: 800 3: 802 4: 801 
Graphics:  Device-1: Intel HD Graphics 620 vendor: ASUSTeK driver: i915 v: kernel bus ID: 00:02.0 
           Device-2: NVIDIA GM108M [GeForce 940MX] vendor: ASUSTeK driver: nouveau v: kernel bus ID: 01:00.0 
           Display: x11 server: X.Org 1.20.4 driver: modesetting resolution: 1920x1080~60Hz 
           OpenGL: renderer: Mesa DRI Intel HD Graphics 620 (Kaby Lake GT2) v: 4.5 Mesa 19.0.4 direct render: Yes 
Audio:     Device-1: Intel Sunrise Point-LP HD Audio vendor: ASUSTeK driver: snd_hda_intel v: kernel bus ID: 00:1f.3 
           Sound Server: ALSA v: k4.20.17-1-MANJARO 
Network:   Device-1: Intel Wireless 8265 / 8275 driver: iwlwifi v: kernel port: e000 bus ID: 02:00.0 
           IF: wlp2s0 state: up mac: <filter> 
Drives:    Local Storage: total: 931.51 GiB used: 136.18 GiB (14.6%) 
           ID-1: /dev/sda vendor: Seagate model: ST1000LM035-1RK172 size: 931.51 GiB 
Partition: ID-1: / size: 608.30 GiB used: 136.16 GiB (22.4%) fs: ext4 dev: /dev/sda6 
Sensors:   System Temperatures: cpu: 49.0 C mobo: N/A 
           Fan Speeds (RPM): N/A 
Info:      Processes: 176 Uptime: 14m Memory: 11.61 GiB used: 1.27 GiB (10.9%) Init: systemd Compilers: gcc: 8.3.0 
           clang: 8.0.0 Shell: zsh v: 5.7.1 inxi: 3.0.34