diff --git a/nixos/modules/services/x11/display-managers/gdm.nix b/nixos/modules/services/x11/display-managers/gdm.nix
index 77e0d9cb06d..8ae5a096bcb 100644
--- a/nixos/modules/services/x11/display-managers/gdm.nix
+++ b/nixos/modules/services/x11/display-managers/gdm.nix
@@ -95,7 +95,7 @@ in
     services.xserver.displayManager.job =
       {
         environment = {
-          GDM_X_SERVER = "${cfg.xserverBin} ${cfg.xserverArgs}";
+          GDM_X_SERVER_EXTRA_ARGS = "${cfg.xserverArgs}";
           GDM_SESSIONS_DIR = "${cfg.session.desktops}";
           # Find the mouse
           XCURSOR_PATH = "~/.icons:${config.system.path}/share/icons";