diff --git a/modules/config/power-management.nix b/modules/config/power-management.nix
index 7497877981c5..b474b3eedcdd 100644
--- a/modules/config/power-management.nix
+++ b/modules/config/power-management.nix
@@ -91,8 +91,9 @@ in
         "p4_clockmod"
       ];
 
-    powerManagement.cpuFreqGovernor = "ondemand";
-    powerManagement.scsiLinkPolicy = "min_power";
+    powerManagement.cpuFreqGovernor = mkDefault "ondemand";
+    powerManagement.scsiLinkPolicy = mkDefault "min_power";
+    
   };
 
 }
diff --git a/modules/tasks/cpu-freq.nix b/modules/tasks/cpu-freq.nix
index b7d9756db1b5..0e0fd502a01c 100644
--- a/modules/tasks/cpu-freq.nix
+++ b/modules/tasks/cpu-freq.nix
@@ -10,6 +10,7 @@ with pkgs.lib;
     powerManagement.cpuFreqGovernor = mkOption {
       default = "";
       example = "ondemand";
+      type = types.uniq types.string;
       description = ''
         Configure the governor used to regulate the frequence of the
         available CPUs. By default, the kernel configures the governor
diff --git a/modules/tasks/scsi-link-power-management.nix b/modules/tasks/scsi-link-power-management.nix
index 4d7a4e740dd8..13b9eca53cb9 100644
--- a/modules/tasks/scsi-link-power-management.nix
+++ b/modules/tasks/scsi-link-power-management.nix
@@ -10,6 +10,7 @@ with pkgs.lib;
     powerManagement.scsiLinkPolicy = mkOption {
       default = "";
       example = "min_power";
+      type = types.uniq types.string;
       description = ''
         Configure the scsi link power management policy. By default,
         the kernel configures "max_performance".