diff --git a/src/emu/debug/debugcpu.c b/src/emu/debug/debugcpu.c
index cdb903f8b99..46dac61306e 100644
--- a/src/emu/debug/debugcpu.c
+++ b/src/emu/debug/debugcpu.c
@@ -144,7 +144,7 @@ int mame_debug_is_active(void)
     on_vblank - called when a VBLANK hits
 -------------------------------------------------*/
 
-static void on_vblank(running_machine *machine, int vblank_state)
+static void on_vblank(const device_config *device, int vblank_state)
 {
 	/* if we're configured to stop on VBLANK, break */
 	if (vblank_state && break_on_vblank)
@@ -296,7 +296,8 @@ void debug_cpu_init(running_machine *machine)
 	}
 
 	/* add callback for breaking on VBLANK */
-	video_screen_register_global_vbl_cb(on_vblank);
+	if (machine->primary_screen != NULL)
+		video_screen_register_vbl_cb(machine->primary_screen, on_vblank);
 
 	add_exit_callback(machine, debug_cpu_exit);
 }
diff --git a/src/emu/mame.c b/src/emu/mame.c
index 8887e583f0e..8d4523e207e 100644
--- a/src/emu/mame.c
+++ b/src/emu/mame.c
@@ -581,7 +581,7 @@ void mame_frame_update(running_machine *machine)
 {
 	callback_item *cb;
 
-	/* call all registered reset callbacks */
+	/* call all registered frame callbacks */
 	for (cb = machine->mame_data->frame_callback_list; cb; cb = cb->next)
 		(*cb->func.frame)(machine);
 }
diff --git a/src/emu/video.c b/src/emu/video.c
index 5af7b4d2b1c..112adfc1b8c 100644
--- a/src/emu/video.c
+++ b/src/emu/video.c
@@ -124,9 +124,6 @@ struct _video_global
 	/* snapshot stuff */
 	render_target *			snap_target;		/* screen shapshot target */
 	bitmap_t *				snap_bitmap;		/* screen snapshot bitmap */
-
-	/* global VBLANK callbacks */
-	vblank_state_changed_global_func vbl_cbs[MAX_VBL_CB];	/* the array of callbacks */
 };
 
 
@@ -1187,39 +1184,6 @@ void video_screen_register_vbl_cb(const device_config *screen, vblank_state_chan
 }
 
 
-/*-------------------------------------------------
-    video_screen_register_global_vbl_cb - registers a
-    VBLANK callback for a specific screen
--------------------------------------------------*/
-
-void video_screen_register_global_vbl_cb(vblank_state_changed_global_func vbl_cb)
-{
-	int i, found;
-
-	/* validate arguments */
-	assert(vbl_cb != NULL);
-
-	/* check if we already have this callback registered */
-	found = FALSE;
-	for (i = 0; i < MAX_VBL_CB; i++)
-	{
-		if (global.vbl_cbs[i] == NULL)
-			break;
-
-		if (global.vbl_cbs[i] == vbl_cb)
-			found = TRUE;
-	}
-
-	/* check that there is room */
-	assert(i != MAX_VBL_CB);
-
-	/* if not found, register and increment count */
-	if (!found)
-		global.vbl_cbs[i] = vbl_cb;
-}
-
-
-
 /***************************************************************************
     VIDEO SCREEN DEVICE INTERFACE
 ***************************************************************************/
@@ -1303,17 +1267,9 @@ static TIMER_CALLBACK( vblank_begin_callback )
 	for (i = 0; internal_state->vbl_cbs[i] != NULL; i++)
 		internal_state->vbl_cbs[i](screen, TRUE);
 
-	/* for the first screen */
-	if (screen == machine->primary_screen)
-	{
-		/* call the global callbacks */
-		for (i = 0; global.vbl_cbs[i] != NULL; i++)
-			global.vbl_cbs[i](machine, TRUE);
-
-		/* do we update the screen now? */
-		if (!(machine->config->video_attributes & VIDEO_UPDATE_AFTER_VBLANK))
-			video_frame_update(machine, FALSE);
-	}
+	/* if this is the primary screen and we need to update now */
+	if ((screen == machine->primary_screen) && !(machine->config->video_attributes & VIDEO_UPDATE_AFTER_VBLANK))
+		video_frame_update(machine, FALSE);
 
 	/* reset the timers */
 	timer_adjust_oneshot(internal_state->vblank_begin_timer, attotime_make(0, internal_state->frame_period), 0);
@@ -1337,17 +1293,9 @@ static TIMER_CALLBACK( vblank_end_callback )
 	for (i = 0; internal_state->vbl_cbs[i] != NULL; i++)
 		internal_state->vbl_cbs[i](screen, FALSE);
 
-	/* for the first screen */
-	if (screen == machine->primary_screen)
-	{
-		/* call the global callbacks */
-		for (i = 0; global.vbl_cbs[i] != NULL; i++)
-			global.vbl_cbs[i](machine, FALSE);
-
-		/* update if we handn't already */
-		if (machine->config->video_attributes & VIDEO_UPDATE_AFTER_VBLANK)
-			video_frame_update(machine, FALSE);
-	}
+	/* if this is the primary screen and we need to update now */
+	if ((screen == machine->primary_screen) && (machine->config->video_attributes & VIDEO_UPDATE_AFTER_VBLANK))
+		video_frame_update(machine, FALSE);
 
 	/* increment the frame number counter */
 	internal_state->frame_number++;
diff --git a/src/emu/video.h b/src/emu/video.h
index 21ab170f2ab..e0473d50f82 100644
--- a/src/emu/video.h
+++ b/src/emu/video.h
@@ -96,14 +96,12 @@ struct _screen_config
 
 
 /*-------------------------------------------------
-    vblank_state_changed_func
-    vblank_state_changed_global_func -
+    vblank_state_changed_func -
     callback that is called to notify of a change
     in the VBLANK state
 -------------------------------------------------*/
 
 typedef void (*vblank_state_changed_func)(const device_config *device, int vblank_state);
-typedef void (*vblank_state_changed_global_func)(running_machine *machine, int vblank_state);
 
 
 
@@ -172,9 +170,6 @@ UINT64 video_screen_get_frame_number(const device_config *screen);
 /* registers a VBLANK callback for the given screen */
 void video_screen_register_vbl_cb(const device_config *screen, vblank_state_changed_func vbl_cb);
 
-/* registers a VBLANK callback independent of a screen  */
-void video_screen_register_global_vbl_cb(vblank_state_changed_global_func vbl_cb);
-
 
 /* ----- video screen device interface ----- */
 
diff --git a/src/emu/watchdog.c b/src/emu/watchdog.c
index 7cf41f5ade3..b68d7085098 100644
--- a/src/emu/watchdog.c
+++ b/src/emu/watchdog.c
@@ -83,18 +83,18 @@ static TIMER_CALLBACK( watchdog_callback )
     timers
 -------------------------------------------------*/
 
-static void on_vblank(running_machine *machine, int vblank_state)
+static void on_vblank(const device_config *screen, int vblank_state)
 {
 	/* VBLANK starting */
 	if (vblank_state && watchdog_enabled)
 	{
 		/* check the watchdog */
-		if (machine->config->watchdog_vblank_count != 0)
+		if (screen->machine->config->watchdog_vblank_count != 0)
 		{
 			watchdog_counter = watchdog_counter - 1;
 
 			if (watchdog_counter == 0)
-				watchdog_callback(machine, NULL, 0);
+				watchdog_callback(screen->machine, NULL, 0);
 		}
 	}
 }
@@ -115,8 +115,9 @@ void watchdog_reset(running_machine *machine)
 	{
 		watchdog_counter = machine->config->watchdog_vblank_count;
 
-		/* register a global VBLANK callback */
-		video_screen_register_global_vbl_cb(on_vblank);
+		/* register a VBLANK callback for the primary screen */
+		if (machine->primary_screen != NULL)
+			video_screen_register_vbl_cb(machine->primary_screen, on_vblank);
 	}
 
 	/* timer-based watchdog? */