diff --git a/services/surfaceflinger/SurfaceFlinger.cpp b/services/surfaceflinger/SurfaceFlinger.cpp
index 88666ea..ab09bfa 100644
--- a/services/surfaceflinger/SurfaceFlinger.cpp
+++ b/services/surfaceflinger/SurfaceFlinger.cpp
@@ -300,6 +300,7 @@
     // start the EventThread
     mEventThread = new EventThread(this);
     mEventQueue.setEventThread(mEventThread);
+    hw.startSleepManagement();
 
     /*
      *  We're now ready to accept clients...