Enable gamemode on GLaDOS

nixos/hosts/GLaDOS/configuration.nix

@@ -46,6 +46,27 @@
     driversi686Linux.amdvlk
   ];
 
+  programs.gamemode = {
+    enable = true;
+    settings = {
+      general = {
+        renice = 10;
+      };
+
+      # Warning: GPU optimisations have the potential to damage hardware
+      gpu = {
+        apply_gpu_optimisations = "accept-responsibility";
+        gpu_device = 0;
+        amd_performance_level = "high";
+      };
+
+      custom = {
+        start = "${pkgs.libnotify}/bin/notify-send 'GameMode started'";
+        end = "${pkgs.libnotify}/bin/notify-send 'GameMode ended'";
+      };
+    };
+  };
+
   boot.loader.systemd-boot.enable = lib.mkForce false;
 
   boot.lanzaboote = {