fixed some formatting and adding nvidia driver module

modules/amd-drivers.nix

@@ -9,14 +9,10 @@ let
   cfg = config.drivers.amdgpu;
 in
 {
-  # Declare what settings a user of this "hello.nix" module CAN SET.
   options.drivers.amdgpu = {
     enable = mkEnableOption "Enable AMD Drivers";
   };
 
-  # Define what other settings, services and resources should be active IF
-  # a user of this "hello.nix" module ENABLED this module 
-  # by setting "services.hello.enable = true;".
   config = mkIf cfg.enable {
     systemd.tmpfiles.rules = [ "L+    /opt/rocm/hip   -    -    -     -    ${pkgs.rocmPackages.clr}" ];
     services.xserver.enable = true;

modules/nvidia-drivers.nix

@@ -0,0 +1,41 @@
+{
+  lib,
+  pkgs,
+  config,
+  ...
+}:
+with lib;
+let
+  cfg = config.drivers.nvidia;
+in
+{
+  options.drivers.nvidia = {
+    enable = mkEnableOption "Enable Nvidia Drivers";
+  };
+
+  config = mkIf cfg.enable {
+    services.xserver.videoDrivers = [ "nvidia" ];
+    hardware.nvidia = {
+      # Modesetting is required.
+      modesetting.enable = true;
+      # Nvidia power management. Experimental, and can cause sleep/suspend to fail.
+      powerManagement.enable = false;
+      # Fine-grained power management. Turns off GPU when not in use.
+      # Experimental and only works on modern Nvidia GPUs (Turing or newer).
+      powerManagement.finegrained = false;
+      # Use the NVidia open source kernel module (not to be confused with the
+      # independent third-party "nouveau" open source driver).
+      # Support is limited to the Turing and later architectures. Full list of
+      # supported GPUs is at:
+      # https://github.com/NVIDIA/open-gpu-kernel-modules#compatible-gpus
+      # Only available from driver 515.43.04+
+      # Currently alpha-quality/buggy, so false is currently the recommended setting.
+      open = false;
+      # Enable the Nvidia settings menu,
+      # accessible via `nvidia-settings`.
+      nvidiaSettings = true;
+      # Optionally, you may need to select the appropriate driver version for your specific GPU.
+      package = config.boot.kernelPackages.nvidiaPackages.stable;
+    };
+  };
+}