diff --git a/src/mame/drivers/polgar.cpp b/src/mame/drivers/polgar.cpp
index 9f1222f8ea2..b2893ac51eb 100644
--- a/src/mame/drivers/polgar.cpp
+++ b/src/mame/drivers/polgar.cpp
@@ -22,9 +22,10 @@ TODO:
 #include "video/hd44780.h"
 #include "speaker.h"
 
-#include "mephisto_lcd.lh"
+// internal artwork
 #include "mephisto_academy.lh"
 #include "mephisto_milano.lh"
+#include "mephisto_polgar.lh"
 
 
 class mephisto_polgar_state : public driver_device
@@ -265,7 +266,7 @@ static INPUT_PORTS_START( polgar )
 	PORT_BIT(0x10, IP_ACTIVE_LOW, IPT_KEYPAD)     PORT_NAME("LEV")    PORT_CODE(KEYCODE_L)
 	PORT_BIT(0x20, IP_ACTIVE_LOW, IPT_KEYPAD)     PORT_NAME("FCT")    PORT_CODE(KEYCODE_F)
 	PORT_BIT(0x40, IP_ACTIVE_LOW, IPT_KEYPAD)     PORT_NAME("ENT")    PORT_CODE(KEYCODE_ENTER)
-	PORT_BIT(0x80, IP_ACTIVE_LOW, IPT_KEYPAD)     PORT_NAME("CL")     PORT_CODE(KEYCODE_BACKSPACE)
+	PORT_BIT(0x80, IP_ACTIVE_LOW, IPT_KEYPAD)     PORT_NAME("CL")     PORT_CODE(KEYCODE_BACKSPACE) PORT_CODE(KEYCODE_DEL)
 INPUT_PORTS_END
 
 void mephisto_risc_state::machine_start()
@@ -313,7 +314,7 @@ void mephisto_polgar_state::polgar(machine_config &config)
 
 	MEPHISTO_SENSORS_BOARD(config, "board");
 	MEPHISTO_DISPLAY_MODUL(config, "display");
-	config.set_default_layout(layout_mephisto_lcd);
+	config.set_default_layout(layout_mephisto_polgar);
 }
 
 void mephisto_polgar_state::polgar10(machine_config &config)
@@ -344,7 +345,7 @@ void mephisto_risc_state::mrisc(machine_config &config)
 
 	MEPHISTO_SENSORS_BOARD(config, "board");
 	MEPHISTO_DISPLAY_MODUL(config, "display");
-	config.set_default_layout(layout_mephisto_lcd);
+	config.set_default_layout(layout_mephisto_polgar);
 }
 
 void mephisto_milano_state::milano(machine_config &config)
diff --git a/src/mame/drivers/saitek_risc2500.cpp b/src/mame/drivers/saitek_risc2500.cpp
index 7bef7e8a201..df3c07fcd16 100644
--- a/src/mame/drivers/saitek_risc2500.cpp
+++ b/src/mame/drivers/saitek_risc2500.cpp
@@ -5,7 +5,8 @@
 Saitek RISC 2500, Mephisto Montreux
 
 The chess engine is also compatible with Tasc's The ChessMachine software.
-Was the hardware+software subcontracted to Tasc? It has similarities with Tasc R30.
+The hardware+software appears to have been subcontracted to Tasc. It has similarities
+with Tasc R30, and the Montreux repair manual schematics footnotes say TASC23C.
 
 notes:
 - holding LEFT+RIGHT on boot load the QC TestMode
@@ -271,7 +272,7 @@ void risc2500_state::risc2500(machine_config &config)
 	ARM(config, m_maincpu, XTAL(28'322'000) / 2); // VY86C010
 	m_maincpu->set_addrmap(AS_PROGRAM, &risc2500_state::risc2500_mem);
 	m_maincpu->set_copro_type(arm_cpu_device::copro_type::VL86C020);
-	m_maincpu->set_periodic_int(FUNC(risc2500_state::irq1_line_hold), attotime::from_hz(256));
+	m_maincpu->set_periodic_int(FUNC(risc2500_state::irq1_line_hold), attotime::from_hz(32.768_kHz_XTAL/128)); // 256Hz
 
 	screen_device &screen(SCREEN(config, "screen", SCREEN_TYPE_LCD));
 	screen.set_refresh_hz(50);
diff --git a/src/mame/drivers/tasc.cpp b/src/mame/drivers/tasc.cpp
index 186ea53d7be..c451ebeea1c 100644
--- a/src/mame/drivers/tasc.cpp
+++ b/src/mame/drivers/tasc.cpp
@@ -213,7 +213,7 @@ void tasc_state::tasc(machine_config &config)
 	ARM(config, m_maincpu, 30_MHz_XTAL);
 	m_maincpu->set_addrmap(AS_PROGRAM, &tasc_state::main_map);
 	m_maincpu->set_copro_type(arm_cpu_device::copro_type::VL86C020);
-	m_maincpu->set_periodic_int(FUNC(tasc_state::irq1_line_hold), attotime::from_hz(256));
+	m_maincpu->set_periodic_int(FUNC(tasc_state::irq1_line_hold), attotime::from_hz(32.768_kHz_XTAL/128)); // 256Hz
 
 	TIMER(config, "disable_bootrom").configure_generic(FUNC(tasc_state::disable_bootrom));
 
diff --git a/src/mame/layout/mephisto_lcd.lay b/src/mame/layout/mephisto_polgar.lay
similarity index 86%
rename from src/mame/layout/mephisto_lcd.lay
rename to src/mame/layout/mephisto_polgar.lay
index 20188bdddf6..1d27904ce04 100644
--- a/src/mame/layout/mephisto_lcd.lay
+++ b/src/mame/layout/mephisto_polgar.lay
@@ -20,22 +20,22 @@
 		</rect>
 	</element>
 
-	<element name="text_1"> <rect><color red="0.56" green="0.33" blue="0.12" /></rect>    <text string="1"><color red="0.01" green="0.01" blue="0.01" /></text> </element>
-	<element name="text_2"> <rect><color red="0.56" green="0.33" blue="0.12" /></rect>    <text string="2"><color red="0.01" green="0.01" blue="0.01" /></text> </element>
-	<element name="text_3"> <rect><color red="0.56" green="0.33" blue="0.12" /></rect>    <text string="3"><color red="0.01" green="0.01" blue="0.01" /></text> </element>
-	<element name="text_4"> <rect><color red="0.56" green="0.33" blue="0.12" /></rect>    <text string="4"><color red="0.01" green="0.01" blue="0.01" /></text> </element>
-	<element name="text_5"> <rect><color red="0.56" green="0.33" blue="0.12" /></rect>    <text string="5"><color red="0.01" green="0.01" blue="0.01" /></text> </element>
-	<element name="text_6"> <rect><color red="0.56" green="0.33" blue="0.12" /></rect>    <text string="6"><color red="0.01" green="0.01" blue="0.01" /></text> </element>
-	<element name="text_7"> <rect><color red="0.56" green="0.33" blue="0.12" /></rect>    <text string="7"><color red="0.01" green="0.01" blue="0.01" /></text> </element>
-	<element name="text_8"> <rect><color red="0.56" green="0.33" blue="0.12" /></rect>    <text string="8"><color red="0.01" green="0.01" blue="0.01" /></text> </element>
-	<element name="text_a"> <rect><color red="0.56" green="0.33" blue="0.12" /></rect>    <text string="A"><color red="0.01" green="0.01" blue="0.01" /></text> </element>
-	<element name="text_b"> <rect><color red="0.56" green="0.33" blue="0.12" /></rect>    <text string="B"><color red="0.01" green="0.01" blue="0.01" /></text> </element>
-	<element name="text_c"> <rect><color red="0.56" green="0.33" blue="0.12" /></rect>    <text string="C"><color red="0.01" green="0.01" blue="0.01" /></text> </element>
-	<element name="text_d"> <rect><color red="0.56" green="0.33" blue="0.12" /></rect>    <text string="D"><color red="0.01" green="0.01" blue="0.01" /></text> </element>
-	<element name="text_e"> <rect><color red="0.56" green="0.33" blue="0.12" /></rect>    <text string="E"><color red="0.01" green="0.01" blue="0.01" /></text> </element>
-	<element name="text_f"> <rect><color red="0.56" green="0.33" blue="0.12" /></rect>    <text string="F"><color red="0.01" green="0.01" blue="0.01" /></text> </element>
-	<element name="text_g"> <rect><color red="0.56" green="0.33" blue="0.12" /></rect>    <text string="G"><color red="0.01" green="0.01" blue="0.01" /></text> </element>
-	<element name="text_h"> <rect><color red="0.56" green="0.33" blue="0.12" /></rect>    <text string="H"><color red="0.01" green="0.01" blue="0.01" /></text> </element>
+	<element name="text_1"> <rect><color red="0.56" green="0.33" blue="0.12" /></rect>    <text string="1"><color red="0.87" green="0.87" blue="0.84" /></text> </element>
+	<element name="text_2"> <rect><color red="0.56" green="0.33" blue="0.12" /></rect>    <text string="2"><color red="0.87" green="0.87" blue="0.84" /></text> </element>
+	<element name="text_3"> <rect><color red="0.56" green="0.33" blue="0.12" /></rect>    <text string="3"><color red="0.87" green="0.87" blue="0.84" /></text> </element>
+	<element name="text_4"> <rect><color red="0.56" green="0.33" blue="0.12" /></rect>    <text string="4"><color red="0.87" green="0.87" blue="0.84" /></text> </element>
+	<element name="text_5"> <rect><color red="0.56" green="0.33" blue="0.12" /></rect>    <text string="5"><color red="0.87" green="0.87" blue="0.84" /></text> </element>
+	<element name="text_6"> <rect><color red="0.56" green="0.33" blue="0.12" /></rect>    <text string="6"><color red="0.87" green="0.87" blue="0.84" /></text> </element>
+	<element name="text_7"> <rect><color red="0.56" green="0.33" blue="0.12" /></rect>    <text string="7"><color red="0.87" green="0.87" blue="0.84" /></text> </element>
+	<element name="text_8"> <rect><color red="0.56" green="0.33" blue="0.12" /></rect>    <text string="8"><color red="0.87" green="0.87" blue="0.84" /></text> </element>
+	<element name="text_a"> <rect><color red="0.56" green="0.33" blue="0.12" /></rect>    <text string="A"><color red="0.87" green="0.87" blue="0.84" /></text> </element>
+	<element name="text_b"> <rect><color red="0.56" green="0.33" blue="0.12" /></rect>    <text string="B"><color red="0.87" green="0.87" blue="0.84" /></text> </element>
+	<element name="text_c"> <rect><color red="0.56" green="0.33" blue="0.12" /></rect>    <text string="C"><color red="0.87" green="0.87" blue="0.84" /></text> </element>
+	<element name="text_d"> <rect><color red="0.56" green="0.33" blue="0.12" /></rect>    <text string="D"><color red="0.87" green="0.87" blue="0.84" /></text> </element>
+	<element name="text_e"> <rect><color red="0.56" green="0.33" blue="0.12" /></rect>    <text string="E"><color red="0.87" green="0.87" blue="0.84" /></text> </element>
+	<element name="text_f"> <rect><color red="0.56" green="0.33" blue="0.12" /></rect>    <text string="F"><color red="0.87" green="0.87" blue="0.84" /></text> </element>
+	<element name="text_g"> <rect><color red="0.56" green="0.33" blue="0.12" /></rect>    <text string="G"><color red="0.87" green="0.87" blue="0.84" /></text> </element>
+	<element name="text_h"> <rect><color red="0.56" green="0.33" blue="0.12" /></rect>    <text string="H"><color red="0.87" green="0.87" blue="0.84" /></text> </element>
 	<element name="text_trn">       <rect><color red="0" green="0" blue="0" /></rect>             <text string="TRN">                    <color red="0.76" green="0.74" blue="0.41" /></text> </element>
 	<element name="text_info">      <rect><color red="0" green="0" blue="0" /></rect>             <text string="INFO">                   <color red="0.76" green="0.74" blue="0.41" /></text> </element>
 	<element name="text_mem">       <rect><color red="0" green="0" blue="0" /></rect>             <text string="MEM">                    <color red="0.76" green="0.74" blue="0.41" /></text> </element>
@@ -44,14 +44,17 @@
 	<element name="text_fct">       <rect><color red="0" green="0" blue="0" /></rect>             <text string="FCT">                    <color red="0.76" green="0.74" blue="0.41" /></text> </element>
 	<element name="text_ent">       <rect><color red="0" green="0" blue="0" /></rect>             <text string="ENT">                    <color red="0.76" green="0.74" blue="0.41" /></text> </element>
 	<element name="text_cl">        <rect><color red="0" green="0" blue="0" /></rect>             <text string="CL">                     <color red="0.76" green="0.74" blue="0.41" /></text> </element>
-	<element name="text_p1">        <rect><color red="0" green="0" blue="0" /></rect>             <text string="[K]">                    <color red="0.76" green="0.74" blue="0.41" /></text> </element>
-	<element name="text_p2">        <rect><color red="0" green="0" blue="0" /></rect>             <text string="[Q]">                    <color red="0.76" green="0.74" blue="0.41" /></text> </element>
-	<element name="text_p3">        <rect><color red="0" green="0" blue="0" /></rect>             <text string="[R]">                    <color red="0.76" green="0.74" blue="0.41" /></text> </element>
-	<element name="text_p4">        <rect><color red="0" green="0" blue="0" /></rect>             <text string="[B]">                    <color red="0.76" green="0.74" blue="0.41" /></text> </element>
-	<element name="text_p5">        <rect><color red="0" green="0" blue="0" /></rect>             <text string="[N]">                    <color red="0.76" green="0.74" blue="0.41" /></text> </element>
-	<element name="text_p6">        <rect><color red="0" green="0" blue="0" /></rect>             <text string="[P]">                    <color red="0.76" green="0.74" blue="0.41" /></text> </element>
 	<element name="text_lcd">       <rect><color red="0" green="0" blue="0" /></rect>             <text string="16/32 BIT DISPLAY MODUL"><color red="0.76" green="0.74" blue="0.41" /></text> </element>
 
+	<element name="static_lcd"><rect><color red="0.5412" green="0.57255" blue="0.5804" /></rect></element>
+	<element name="yellow_mask"><rect><color red="0.76" green="0.74" blue="0.41" /></rect></element>
+	<element name="text_p1"><image file="chess/wk.png"/></element>
+	<element name="text_p2"><image file="chess/wq.png"/></element>
+	<element name="text_p3"><image file="chess/wr.png"/></element>
+	<element name="text_p4"><image file="chess/wb.png"/></element>
+	<element name="text_p5"><image file="chess/wn.png"/></element>
+	<element name="text_p6"><image file="chess/wp.png"/></element>
+
 
 	<element name="piece" defstate="0">
 		<image file="chess/wp.png" state="1"/>
@@ -356,7 +359,9 @@
 
 	<group name="panel">
 		<bounds left="0" right="60" top="0" bottom="14" />
-		<screen index="0"><bounds x="1" y="3" width="24" height="4.5" /></screen>
+
+		<element ref="static_lcd"><bounds x="1" y="3" width="24.5" height="6.5" /></element>
+		<screen index="0" blend="alpha"><bounds x="1.25" y="4" width="24" height="4.5" /></screen>
 		<bezel element="text_lcd">          <bounds x="1" y="0.5" width="24" height="1.5" />    </bezel>
 
 		<bezel name="led100" element="led">     <bounds x="29.1" y="1" width="1.3" height="1.3" />    </bezel>
@@ -375,12 +380,13 @@
 		<bezel element="text_ent">          <bounds x="49.5" y="8" width="3.5" height="1.2" />  </bezel>
 		<bezel element="text_cl">           <bounds x="54.5" y="8" width="3.5" height="1.3" />  </bezel>
 
-		<bezel element="text_p6">           <bounds x="29.5" y="5.55" width="3.5" height="1.7" /></bezel>
-		<bezel element="text_p5">           <bounds x="34.5" y="5.55" width="3.5" height="1.7" /></bezel>
-		<bezel element="text_p4">           <bounds x="39.5" y="5.55" width="3.5" height="1.7" /></bezel>
-		<bezel element="text_p3">           <bounds x="44.5" y="5.55" width="3.5" height="1.7" /></bezel>
-		<bezel element="text_p2">           <bounds x="49.5" y="5.55" width="3.5" height="1.7" /></bezel>
-		<bezel element="text_p1">           <bounds x="54.5" y="5.55" width="3.5" height="1.7" /></bezel>
+		<element ref="text_p6">           <bounds x="30.25" y="5.55" width="2" height="2" /></element>
+		<element ref="text_p5">           <bounds x="35.25" y="5.55" width="2" height="2" /></element>
+		<element ref="text_p4">           <bounds x="40.25" y="5.55" width="2" height="2" /></element>
+		<element ref="text_p3">           <bounds x="45.25" y="5.55" width="2" height="2" /></element>
+		<element ref="text_p2">           <bounds x="50.25" y="5.55" width="2" height="2" /></element>
+		<element ref="text_p1">           <bounds x="55.25" y="5.55" width="2" height="2" /></element>
+		<element ref="yellow_mask" blend="multiply"><bounds x="30" y="5.51" width="28" height="2.2" /></element>
 
 		<bezel element="hlb" inputtag="KEY" inputmask="0x01">       <bounds x="29.5" y="3" width="3.5" height="2.5" />  </bezel>
 		<bezel element="hlb" inputtag="KEY" inputmask="0x02">       <bounds x="34.5" y="3" width="3.5" height="2.5" />  </bezel>
@@ -393,20 +399,20 @@
 	</group>
 
 	<view name="Internal Layout">
-		<bounds left="0" right="101" top="0" bottom="103" />
+		<bounds left="0" right="101" top="0" bottom="101.5" />
 		<bezel element="cblack"><bounds x="14" y="0" width="87" height="87" /></bezel>
 		<bezel element="cwhite"><bounds x="17" y="2" width="81" height="81" /></bezel>
 
 	<!-- chessboard coords -->
 
-		<bezel element="text_8"><bounds x="14.2" y="7" width="2" height="2" /></bezel>
-		<bezel element="text_7"><bounds x="14.2" y="17" width="2" height="2" /></bezel>
-		<bezel element="text_6"><bounds x="14.2" y="27" width="2" height="2" /></bezel>
-		<bezel element="text_5"><bounds x="14.2" y="37" width="2" height="2" /></bezel>
-		<bezel element="text_4"><bounds x="14.2" y="47" width="2" height="2" /></bezel>
-		<bezel element="text_3"><bounds x="14.2" y="57" width="2" height="2" /></bezel>
-		<bezel element="text_2"><bounds x="14.2" y="67" width="2" height="2" /></bezel>
-		<bezel element="text_1"><bounds x="14.2" y="77" width="2" height="2" /></bezel>
+		<bezel element="text_8"><bounds x="14.7" y="7" width="2" height="2" /></bezel>
+		<bezel element="text_7"><bounds x="14.7" y="17" width="2" height="2" /></bezel>
+		<bezel element="text_6"><bounds x="14.7" y="27" width="2" height="2" /></bezel>
+		<bezel element="text_5"><bounds x="14.7" y="37" width="2" height="2" /></bezel>
+		<bezel element="text_4"><bounds x="14.7" y="47" width="2" height="2" /></bezel>
+		<bezel element="text_3"><bounds x="14.7" y="57" width="2" height="2" /></bezel>
+		<bezel element="text_2"><bounds x="14.7" y="67" width="2" height="2" /></bezel>
+		<bezel element="text_1"><bounds x="14.7" y="77" width="2" height="2" /></bezel>
 
 		<bezel element="text_a"><bounds x="21.5" y="84" width="2" height="2" /></bezel>
 		<bezel element="text_b"><bounds x="31.5" y="84" width="2" height="2" /></bezel>
@@ -418,7 +424,7 @@
 		<bezel element="text_h"><bounds x="91.5" y="84" width="2" height="2" /></bezel>
 
 	<!-- LCD panel -->
-		<group ref="panel"><bounds x="40" y="88" width="60" height="14" /></group>
+		<group ref="panel"><bounds x="40" y="87.5" width="60" height="14" /></group>
 
 		<group ref="sb_board"><bounds x="17.5" y="2.5" width="80" height="80" /></group>
 		<group ref="sb_ui"><bounds x="1.5" y="3" width="10" height="80" /></group>