Please make sure next time you properly format the text when posting it on the forum.
.nvidia-settings-rc should belong to you as user, not root (just mentioning it)
Try this config:
Section "ServerLayout"
Identifier "Layout0"
Screen 0 "Screen0" 0 0
InputDevice "Keyboard0" "CoreKeyboard"
InputDevice "Mouse0" "CorePointer"
Option "Xinerama" "0"
EndSection
Section "Files"
EndSection
Section "Module"
Load "dbe"
Load "extmod"
Load "type1"
Load "freetype"
Load "glx"
EndSection
Section "InputDevice"
# generated from default
Identifier "Mouse0"
Driver "mouse"
Option "Protocol" "auto"
Option "Device" "/dev/psaux"
Option "Emulate3Buttons" "no"
Option "ZAxisMapping" "4 5"
EndSection
Section "InputDevice"
# generated from default
Identifier "Keyboard0"
Driver "kbd"
EndSection
Section "Monitor"
Identifier "Monitor0"
VendorName "DELL"
ModelName "DELL S2721DGF"
HorizSync 250.0 - 250.0
VertRefresh 48.0 - 165.0
Option "DPMS"
EndSection
Section "Device"
Identifier "Device0"
Driver "nvidia"
VendorName "NVIDIA Corporation"
BoardName "NVIDIA GeForce GTX 1660"
Option "ConnectToAcpid" "Off"
EndSection
Section "Screen"
Identifier "Screen0"
Device "Device0"
Monitor "Monitor0"
DefaultDepth 24
Option "Stereo" "0"
Option "nvidiaXineramaInfoOrder" "DFP-0"
Option "metamodes" "DP-2: 2560x1440_165 +2560+0 {ForceCompositionPipeline=On}, DP-0: 2560x1440_165 +0+0 {ForceCompositionPipeline=On}"
Option "SLI" "Off"
Option "MultiGPU" "Off"
Option "BaseMosaic" "off"
SubSection "Display"
Depth 24
EndSubSection
EndSection
Section "Extensions"
Option "COMPOSITE" "Enable"
EndSection
Section "InputClass"
Identifier "Keyboard Defaults"
MatchIsKeyboard "yes"
Option "XkbOptions" "terminate:ctrl_alt_bksp"
EndSection
Make a backup of yours first.