diff --git a/src/mame/drivers/iqblock.c b/src/mame/drivers/iqblock.c
index 6c6d367ddd3..b16008a1b5b 100644
--- a/src/mame/drivers/iqblock.c
+++ b/src/mame/drivers/iqblock.c
@@ -92,11 +92,6 @@ WRITE8_MEMBER(iqblock_state::iqblock_irqack_w)
 	m_maincpu->set_input_line(0, CLEAR_LINE);
 }
 
-READ8_MEMBER(iqblock_state::extrarom_r)
-{
-	return memregion("user1")->base()[offset];
-}
-
 
 WRITE8_MEMBER(iqblock_state::port_C_w)
 {
@@ -120,16 +115,15 @@ ADDRESS_MAP_END
 static ADDRESS_MAP_START( main_portmap, AS_IO, 8, iqblock_state )
 	AM_RANGE(0x2000, 0x23ff) AM_DEVWRITE("palette", palette_device, write) AM_SHARE("palette")
 	AM_RANGE(0x2800, 0x2bff) AM_DEVWRITE("palette", palette_device, write_ext) AM_SHARE("palette_ext")
-	AM_RANGE(0x6000, 0x603f) AM_WRITE(iqblock_fgscroll_w)
-	AM_RANGE(0x6800, 0x69ff) AM_WRITE(iqblock_fgvideoram_w) /* initialized up to 6fff... bug or larger tilemap? */
-	AM_RANGE(0x7000, 0x7fff) AM_WRITE(iqblock_bgvideoram_w)
 	AM_RANGE(0x5080, 0x5083) AM_DEVREADWRITE("ppi8255", i8255_device, read, write)
 	AM_RANGE(0x5090, 0x5090) AM_READ_PORT("SW0")
 	AM_RANGE(0x50a0, 0x50a0) AM_READ_PORT("SW1")
 	AM_RANGE(0x50b0, 0x50b1) AM_DEVWRITE("ymsnd", ym2413_device, write) // UM3567_data_port_0_w
 	AM_RANGE(0x50c0, 0x50c0) AM_WRITE(iqblock_irqack_w)
-	AM_RANGE(0x7000, 0x7fff) AM_READ(iqblock_bgvideoram_r)
-	AM_RANGE(0x8000, 0xffff) AM_READ(extrarom_r)
+	AM_RANGE(0x6000, 0x603f) AM_WRITE(iqblock_fgscroll_w)
+	AM_RANGE(0x6800, 0x69ff) AM_WRITE(iqblock_fgvideoram_w) AM_SHARE("fgvideoram") /* initialized up to 6fff... bug or larger tilemap? */
+	AM_RANGE(0x7000, 0x7fff) AM_RAM_WRITE(iqblock_bgvideoram_w) AM_SHARE("bgvideoram")
+	AM_RANGE(0x8000, 0xffff) AM_ROM AM_REGION("user1", 0)
 ADDRESS_MAP_END
 
 static INPUT_PORTS_START( iqblock )
@@ -433,11 +427,6 @@ DRIVER_INIT_MEMBER(iqblock_state,iqblock)
 		if ((i & 0x0090) == 0x0010) rom[i] ^= 0x20;
 	}
 
-	/* initialize pointers for I/O mapped RAM */
-	m_generic_paletteram_8.set_target(rom + 0x12000, 0x800);
-	m_generic_paletteram2_8.set_target(rom + 0x12800, 0x800);
-	m_fgvideoram = rom + 0x16800;
-	m_bgvideoram = rom + 0x17000;
 	m_maincpu->space(AS_PROGRAM).install_write_handler(0xfe26, 0xfe26, write8_delegate(FUNC(iqblock_state::iqblock_prot_w),this));
 	m_video_type=1;
 }
@@ -455,11 +444,6 @@ DRIVER_INIT_MEMBER(iqblock_state,grndtour)
 		if ((i & 0x0060) == 0x0040) rom[i] ^= 0x20;
 	}
 
-	/* initialize pointers for I/O mapped RAM */
-	m_generic_paletteram_8.set_target(rom + 0x12000, 0x800);
-	m_generic_paletteram2_8.set_target(rom + 0x12800, 0x800);
-	m_fgvideoram = rom + 0x16800;
-	m_bgvideoram = rom + 0x17000;
 	m_maincpu->space(AS_PROGRAM).install_write_handler(0xfe39, 0xfe39, write8_delegate(FUNC(iqblock_state::grndtour_prot_w),this));
 	m_video_type=0;
 }
diff --git a/src/mame/includes/galaxian.h b/src/mame/includes/galaxian.h
index bd92b0e269f..1d7731951cd 100644
--- a/src/mame/includes/galaxian.h
+++ b/src/mame/includes/galaxian.h
@@ -54,8 +54,7 @@ public:
 			m_videoram(*this, "videoram"),
 			m_gfxdecode(*this, "gfxdecode"),
 			m_screen(*this, "screen"),
-			m_palette(*this, "palette"),
-			m_generic_paletteram_16(*this, "paletteram") { }
+			m_palette(*this, "palette") { }
 
 	required_device<cpu_device> m_maincpu;
 	optional_device<cpu_device> m_audiocpu;
@@ -74,7 +73,6 @@ public:
 	required_device<gfxdecode_device> m_gfxdecode;
 	required_device<screen_device> m_screen;
 	required_device<palette_device> m_palette;
-	required_shared_ptr<UINT16> m_generic_paletteram_16;
 
 	int m_bullets_base;
 	int m_sprites_base;
diff --git a/src/mame/includes/iqblock.h b/src/mame/includes/iqblock.h
index 26b95e39b34..f072368c217 100644
--- a/src/mame/includes/iqblock.h
+++ b/src/mame/includes/iqblock.h
@@ -4,19 +4,17 @@ public:
 	iqblock_state(const machine_config &mconfig, device_type type, const char *tag)
 		: driver_device(mconfig, type, tag),
 		m_maincpu(*this,"maincpu"),
-		m_rambase(*this, "rambase"),
 		m_gfxdecode(*this, "gfxdecode"),
-		m_generic_paletteram_8(*this, "paletteram"),
-		m_generic_paletteram2_8(*this, "paletteram2") { }
+		m_rambase(*this, "rambase"),
+		m_bgvideoram(*this, "bgvideoram"),
+		m_fgvideoram(*this, "fgvideoram") { }
 
 	required_device<cpu_device> m_maincpu;
-	required_shared_ptr<UINT8> m_rambase;
 	required_device<gfxdecode_device> m_gfxdecode;
-	required_shared_ptr<UINT8> m_generic_paletteram_8;
-	required_shared_ptr<UINT8> m_generic_paletteram2_8;
+	required_shared_ptr<UINT8> m_rambase;
+	required_shared_ptr<UINT8> m_bgvideoram;
+	required_shared_ptr<UINT8> m_fgvideoram;
 
-	UINT8 *m_bgvideoram;
-	UINT8 *m_fgvideoram;
 	int m_videoenable;
 	int m_video_type;
 	tilemap_t *m_bg_tilemap;
@@ -25,10 +23,8 @@ public:
 	DECLARE_WRITE8_MEMBER(iqblock_prot_w);
 	DECLARE_WRITE8_MEMBER(grndtour_prot_w);
 	DECLARE_WRITE8_MEMBER(iqblock_irqack_w);
-	DECLARE_READ8_MEMBER(extrarom_r);
 	DECLARE_WRITE8_MEMBER(iqblock_fgvideoram_w);
 	DECLARE_WRITE8_MEMBER(iqblock_bgvideoram_w);
-	DECLARE_READ8_MEMBER(iqblock_bgvideoram_r);
 	DECLARE_WRITE8_MEMBER(iqblock_fgscroll_w);
 	DECLARE_WRITE8_MEMBER(port_C_w);
 	DECLARE_DRIVER_INIT(grndtour);
diff --git a/src/mame/video/iqblock.c b/src/mame/video/iqblock.c
index fc9bc21e9e2..e88605cbe2b 100644
--- a/src/mame/video/iqblock.c
+++ b/src/mame/video/iqblock.c
@@ -63,11 +63,6 @@ WRITE8_MEMBER(iqblock_state::iqblock_bgvideoram_w)
 	m_bg_tilemap->mark_tile_dirty(offset & 0x7ff);
 }
 
-READ8_MEMBER(iqblock_state::iqblock_bgvideoram_r)
-{
-	return m_bgvideoram[offset];
-}
-
 WRITE8_MEMBER(iqblock_state::iqblock_fgscroll_w)
 {
 	m_fg_tilemap->set_scrolly(offset,data);