diff --git a/src/add-ons/accelerants/nvidia/ProposeDisplayMode.c b/src/add-ons/accelerants/nvidia/ProposeDisplayMode.c
index 7129155364..9387b30a20 100644
--- a/src/add-ons/accelerants/nvidia/ProposeDisplayMode.c
+++ b/src/add-ons/accelerants/nvidia/ProposeDisplayMode.c
@@ -4,7 +4,7 @@
 
 	Other authors for NV driver:
 	Mark Watson,
-	Rudolf Cornelissen 9/2002-2/2005
+	Rudolf Cornelissen 9/2002-10/2005
 */
 
 #define MODULE_BIT 0x00400000
@@ -503,15 +503,9 @@ status_t PROPOSE_DISPLAY_MODE(display_mode *target, const display_mode *low, con
 	}
 
 	/* set TV_CAPABLE if suitable: pixelclock is not important (defined by TVstandard) */
-	//fixme: modify for G100 and G200 TVout later on...
-	if (target->flags & DUALHEAD_CAPABLE)
+	if (si->ps.tvout && BT_check_tvmode(*target))
 	{
-		if (si->ps.tvout &&
-			(target->timing.h_display <= 1024) &&
-			(target->timing.v_display <= 768))
-		{
-			target->flags |= TV_CAPABLE;
-		}
+		target->flags |= TV_CAPABLE;
 	}
 
 	/* set HARDWARE_CURSOR mode if suitable */
diff --git a/src/add-ons/accelerants/nvidia/SetDisplayMode.c b/src/add-ons/accelerants/nvidia/SetDisplayMode.c
index 8521cc7fbc..5200f0b28d 100644
--- a/src/add-ons/accelerants/nvidia/SetDisplayMode.c
+++ b/src/add-ons/accelerants/nvidia/SetDisplayMode.c
@@ -6,7 +6,7 @@
 	Other authors:
 	Mark Watson,
 	Apsed,
-	Rudolf Cornelissen 11/2002-6/2005
+	Rudolf Cornelissen 11/2002-10/2005
 */
 
 #define MODULE_BIT 0x00200000
@@ -112,7 +112,8 @@ status_t SET_DISPLAY_MODE(display_mode *mode_to_set)
 		LOG(1,("SETMODE: setting DUALHEAD mode\n"));
 
 		/* validate flags for secondary TVout */
-		if ((i2c_sec_tv_adapter() != B_OK) && (target2.flags & TV_BITS))
+		//fixme: remove or block on autodetect fail. (is now shutoff)
+		if ((0) && (target2.flags & TV_BITS))
 		{
 			target.flags &= ~TV_BITS;//still needed for some routines...
 			target2.flags &= ~TV_BITS;
@@ -209,6 +210,7 @@ status_t SET_DISPLAY_MODE(display_mode *mode_to_set)
 		}
 
 		/* check if we are doing interlaced TVout mode */
+		//fixme: we don't support interlaced mode?
 		si->interlaced_tv_mode = false;
 /*		if ((target2.flags & TV_BITS) && (si->ps.card_type >= G450))
 			si->interlaced_tv_mode = true;
@@ -242,7 +244,7 @@ status_t SET_DISPLAY_MODE(display_mode *mode_to_set)
 		if (!(target2.flags & TV_BITS))	result = head2_set_timing(target2);
 
 		/* TVout support: setup CRTC2 and it's pixelclock */
-		if (si->ps.tvout && (target2.flags & TV_BITS)) maventv_init(target2);
+		if (si->ps.tvout && (target2.flags & TV_BITS)) BT_setmode(target2);
 	}
 	else /* single head mode */
 	{
@@ -306,7 +308,10 @@ status_t SET_DISPLAY_MODE(display_mode *mode_to_set)
 		head1_set_display_start(startadd,colour_depth1);
 
 		/* set the timing */
-		head1_set_timing(target);
+		if (!(target.flags & TV_BITS)) head1_set_timing(target);
+
+		/* TVout support: setup CRTC and it's pixelclock */
+		if (si->ps.tvout && (target.flags & TV_BITS)) BT_setmode(target);
 
 		//fixme: shut-off the videoPLL if it exists...
 	}
diff --git a/src/add-ons/accelerants/nvidia/engine/nv_brooktreetv.c b/src/add-ons/accelerants/nvidia/engine/nv_brooktreetv.c
index 139bf5cc4c..a506155ab1 100644
--- a/src/add-ons/accelerants/nvidia/engine/nv_brooktreetv.c
+++ b/src/add-ons/accelerants/nvidia/engine/nv_brooktreetv.c
@@ -1,6 +1,6 @@
 /*
 	Author:
-	Rudolf Cornelissen 4/2002-9/2005
+	Rudolf Cornelissen 4/2002-10/2005
 */
 
 #define MODULE_BIT 0x00100000
@@ -15,7 +15,7 @@
 //fixme: remove rubbish..
 enum
 {	// TVoutput mode to set
-	NOT_USED = 0,
+	NOT_SUPPORTED = 0,
 	NTSC640_TST,
 	NTSC640,
 	NTSC800,
@@ -1268,20 +1268,86 @@ static uint8 BT_killclk_blackout(void)
 	return stat;
 }//end BT_killclk_blackout.
 
-//fixme: resetup for brooktreetv, should cover all supported encoders later on..
-int maventv_init(display_mode target)
+uint8 BT_check_tvmode(display_mode target)
 {
+	uint8 status = NOT_SUPPORTED;
+	uint32 mode = ((target.timing.h_display) | ((target.timing.v_display) << 16));
+
+	switch (mode)
+	{
+	case (640 | (480 << 16)):
+		if ((target.flags & TV_BITS) == TV_PAL)
+		{
+			if (!(target.flags & TV_VIDEO)) status = PAL640;
+		}
+		if ((target.flags & TV_BITS) == TV_NTSC)
+		{
+			if (!(target.flags & TV_VIDEO)) status = NTSC640;
+			else status = NTSC640_OS;
+		}
+		break;
+	case (800 | (600 << 16)):
+		if ((target.flags & TV_BITS) == TV_PAL)
+		{
+			if (!(target.flags & TV_VIDEO)) status = PAL800;
+			else status = PAL800_OS;
+		}
+		if ((target.flags & TV_BITS) == TV_NTSC)
+		{
+			if (!(target.flags & TV_VIDEO)) status = NTSC800;
+		}
+		break;
+	case (720 | (480 << 16)):
+		if (((target.flags & TV_BITS) == TV_NTSC) && (target.flags & TV_VIDEO))
+			status = NTSC720;
+		break;
+	case (720 | (576 << 16)):
+		if (((target.flags & TV_BITS) == TV_PAL) && (target.flags & TV_VIDEO))
+			status = PAL720;
+		break;
+	}
+
+	return status;
+}//end BT_check_tvmode.
+
+status_t BT_setmode(display_mode target)
+{
+	uint8 tvmode;
+
 	/* use a display_mode copy because we might tune it for TVout compatibility */
 	display_mode tv_target = target;
 
 	/* preset new TVout mode */
-	if ((tv_target.flags & TV_BITS) == TV_PAL)
+	tvmode = BT_check_tvmode(tv_target);
+	if (!tvmode) return B_ERROR;
+
+//fixme: only testing singlehead cards for now...
+if (si->ps.secondary_head)
+{
+	head1_set_timing(tv_target);
+	return B_ERROR;
+}
+
+	switch (tvmode)
 	{
-		LOG(4, ("MAVENTV: PAL TVout\n"));
-	}
-	else
-	{
-		LOG(4, ("MAVENTV: NTSC TVout\n"));
+	case NTSC640:
+	case NTSC640_TST:
+		break;
+	case NTSC800:
+		break;
+	case PAL640:
+		break;
+	case PAL800:
+	case PAL800_TST:
+		break;
+	case NTSC640_OS:
+		break;
+	case PAL800_OS:
+		break;
+	case NTSC720:
+		break;
+	case PAL720:
+		break;
 	}
 
 	/* tune new TVout mode */
@@ -1295,9 +1361,9 @@ int maventv_init(display_mode target)
 	/* program new TVout mode */
 
 	/* setup CRTC timing */
-	head2_set_timing(tv_target);
+	head1_set_timing(tv_target);
 
 	/* start whole thing if needed */
 
-	return 0;
+	return B_OK;
 }
diff --git a/src/add-ons/accelerants/nvidia/engine/nv_i2c.c b/src/add-ons/accelerants/nvidia/engine/nv_i2c.c
index 641e478f65..8cb8b02944 100644
--- a/src/add-ons/accelerants/nvidia/engine/nv_i2c.c
+++ b/src/add-ons/accelerants/nvidia/engine/nv_i2c.c
@@ -2,42 +2,13 @@
  * i2c interface.
  * Bus should be run at max. 100kHz: see original Philips I2C specification
  *	
- * Rudolf Cornelissen 12/2002-9/2005
+ * Rudolf Cornelissen 12/2002-10/2005
  */
 
 #define MODULE_BIT 0x00004000
 
 #include "nv_std.h"
 
-status_t i2c_sec_tv_adapter()
-{
-	status_t result = B_ERROR;
-
-	/* The secondary DDC channel only exist on dualhead cards */
-	if (!si->ps.secondary_head) return result;
-
-	/* make sure the output lines will be active-low when enabled
-	 * (they will be pulled 'passive-high' when disabled) */
-//	DXIW(GENIODATA,0x00);
-	/* send out B_STOP condition on secondary head DDC channel and use it to
-	 * check for 'shortcut', indicating the Matrox VGA->TV adapter is connected */
-
-	/* make sure SDA is low */
-//	DXIW(GENIOCTRL, (DXIR(GENIOCTRL) | DDC2_DATA));
-	snooze(2);
-	/* make sure SCL should be high */
-//	DXIW(GENIOCTRL, (DXIR(GENIOCTRL) & ~DDC2_CLK));
-	snooze(2);
-	/* if SCL is low then the bus is blocked by a TV adapter */
-//	if (!(DXIR(GENIODATA) & DDC2_CLK)) result = B_OK;
-	snooze(5);
-	/* set SDA while SCL should be set (generates actual bus-stop condition) */
-//	DXIW(GENIOCTRL, (DXIR(GENIOCTRL) & ~DDC2_DATA));
-	snooze(5);
-
-	return result;
-}
-
 char i2c_flag_error (char ErrNo)
 //error code list:
 //0 - OK status
diff --git a/src/add-ons/accelerants/nvidia/engine/nv_proto.h b/src/add-ons/accelerants/nvidia/engine/nv_proto.h
index 3fbf185e02..1f5c7e1d74 100644
--- a/src/add-ons/accelerants/nvidia/engine/nv_proto.h
+++ b/src/add-ons/accelerants/nvidia/engine/nv_proto.h
@@ -60,7 +60,8 @@ status_t nv_dac2_set_pix_pll(display_mode target);
 
 /* Brooktree TV functions */
 bool BT_probe(void);
-int maventv_init(display_mode target);
+uint8 BT_check_tvmode(display_mode target);
+status_t BT_setmode(display_mode target);
 
 /* CRTC1 functions */
 status_t nv_crtc_update_fifo(void);