Index: source/d_net.c
===================================================================
--- source/d_net.c	(revision 946)
+++ source/d_net.c	(working copy)
@@ -983,6 +983,9 @@
          D_ProcessEvents();
       }
       
+      // Sleep until a tic is available, so we don't hog the CPU.
+      SDL_Delay(1);
+
       return;
    }