diff --git a/src/mame/drivers/argo.cpp b/src/mame/drivers/argo.cpp
index 1750e5d87bf..eccf3a1447e 100644
--- a/src/mame/drivers/argo.cpp
+++ b/src/mame/drivers/argo.cpp
@@ -46,7 +46,7 @@ public:
 	DECLARE_WRITE8_MEMBER(argo_videoram_w);
 	DECLARE_READ8_MEMBER(argo_io_r);
 	DECLARE_WRITE8_MEMBER(argo_io_w);
-	uint32_t screen_update(screen_device &screen, bitmap_ind16 &bitmap, const rectangle &cliprect);
+	uint32_t screen_update(screen_device &screen, bitmap_rgb32 &bitmap, const rectangle &cliprect);
 	void init_argo();
 
 	void argo(machine_config &config);
@@ -289,7 +289,7 @@ void argo_state::init_argo()
 	membank("boot")->configure_entries(0, 2, &RAM[0x0000], 0xf800);
 }
 
-uint32_t argo_state::screen_update(screen_device &screen, bitmap_ind16 &bitmap, const rectangle &cliprect)
+uint32_t argo_state::screen_update(screen_device &screen, bitmap_rgb32 &bitmap, const rectangle &cliprect)
 {
 	uint8_t y,ra,chr,gfx;
 	uint16_t sy=0,ma=0,x;
@@ -301,7 +301,7 @@ uint32_t argo_state::screen_update(screen_device &screen, bitmap_ind16 &bitmap,
 	{
 		for (ra = 0; ra < 10; ra++)
 		{
-			uint16_t *p = &bitmap.pix16(sy++);
+			uint32_t *p = &bitmap.pix32(sy++);
 
 			for (x = 1; x < 81; x++) // align x to the cursor position numbers
 			{
@@ -325,14 +325,14 @@ uint32_t argo_state::screen_update(screen_device &screen, bitmap_ind16 &bitmap,
 					gfx = 0xff;
 
 				/* Display a scanline of a character */
-				*p++ = BIT(gfx, 7);
-				*p++ = BIT(gfx, 6);
-				*p++ = BIT(gfx, 5);
-				*p++ = BIT(gfx, 4);
-				*p++ = BIT(gfx, 3);
-				*p++ = BIT(gfx, 2);
-				*p++ = BIT(gfx, 1);
-				*p++ = BIT(gfx, 0);
+				*p++ = BIT(gfx, 7) ? rgb_t::white() : rgb_t::black();
+				*p++ = BIT(gfx, 6) ? rgb_t::white() : rgb_t::black();
+				*p++ = BIT(gfx, 5) ? rgb_t::white() : rgb_t::black();
+				*p++ = BIT(gfx, 4) ? rgb_t::white() : rgb_t::black();
+				*p++ = BIT(gfx, 3) ? rgb_t::white() : rgb_t::black();
+				*p++ = BIT(gfx, 2) ? rgb_t::white() : rgb_t::black();
+				*p++ = BIT(gfx, 1) ? rgb_t::white() : rgb_t::black();
+				*p++ = BIT(gfx, 0) ? rgb_t::white() : rgb_t::black();
 			}
 		}
 
@@ -360,9 +360,6 @@ MACHINE_CONFIG_START(argo_state::argo)
 	MCFG_SCREEN_UPDATE_DRIVER(argo_state, screen_update)
 	MCFG_SCREEN_SIZE(640, 250)
 	MCFG_SCREEN_VISIBLE_AREA(0, 639, 0, 249)
-	MCFG_SCREEN_PALETTE("palette")
-
-	MCFG_PALETTE_ADD_MONOCHROME("palette")
 MACHINE_CONFIG_END
 
 /* ROM definition */
diff --git a/src/mame/drivers/cat.cpp b/src/mame/drivers/cat.cpp
index 0f26aab7418..02e065508eb 100644
--- a/src/mame/drivers/cat.cpp
+++ b/src/mame/drivers/cat.cpp
@@ -292,7 +292,7 @@ public:
 	DECLARE_VIDEO_START(cat);
 	void init_cat();
 
-	uint32_t screen_update_cat(screen_device &screen, bitmap_ind16 &bitmap, const rectangle &cliprect);
+	uint32_t screen_update_cat(screen_device &screen, bitmap_rgb32 &bitmap, const rectangle &cliprect);
 
 	DECLARE_WRITE_LINE_MEMBER(cat_duart_irq_handler);
 	DECLARE_WRITE_LINE_MEMBER(cat_duart_txa);
@@ -946,29 +946,29 @@ VIDEO_START_MEMBER(cat_state,cat)
 {
 }
 
-uint32_t cat_state::screen_update_cat(screen_device &screen, bitmap_ind16 &bitmap, const rectangle &cliprect)
+uint32_t cat_state::screen_update_cat(screen_device &screen, bitmap_rgb32 &bitmap, const rectangle &cliprect)
 {
-	uint16_t code;
-	int y, x, b;
+	const rgb_t on_color = m_video_invert ? rgb_t::black() : rgb_t::white();
+	const rgb_t off_color = m_video_invert ? rgb_t::white() : rgb_t::black();
 
 	int addr = 0;
 	if (m_video_enable == 1)
 	{
-		for (y = 0; y < 344; y++)
+		for (int y = 0; y < 344; y++)
 		{
 			int horpos = 0;
-			for (x = 0; x < 42; x++)
+			for (int x = 0; x < 42; x++)
 			{
-				code = m_p_cat_videoram[addr++];
-				for (b = 15; b >= 0; b--)
+				uint16_t code = m_p_cat_videoram[addr++];
+				for (int b = 15; b >= 0; b--)
 				{
-					bitmap.pix16(y, horpos++) = ((code >> b) & 0x01) ^ m_video_invert;
+					bitmap.pix32(y, horpos++) = BIT(code, b) ? on_color : off_color;
 				}
 			}
 		}
 	} else {
 		const rectangle black_area(0, 672 - 1, 0, 344 - 1);
-		bitmap.fill(0, black_area);
+		bitmap.fill(rgb_t::black(), black_area);
 	}
 	return 0;
 }
@@ -1071,9 +1071,6 @@ MACHINE_CONFIG_START(cat_state::cat)
 	MCFG_SCREEN_SIZE(672, 344)
 	MCFG_SCREEN_VISIBLE_AREA(0, 672-1, 0, 344-1)
 	MCFG_SCREEN_UPDATE_DRIVER(cat_state, screen_update_cat)
-	MCFG_SCREEN_PALETTE("palette")
-
-	MCFG_PALETTE_ADD_MONOCHROME("palette")
 
 	MCFG_VIDEO_START_OVERRIDE(cat_state,cat)