diff --git a/src/mame/drivers/compis.cpp b/src/mame/drivers/compis.cpp
index 088011a1834..c919817719e 100644
--- a/src/mame/drivers/compis.cpp
+++ b/src/mame/drivers/compis.cpp
@@ -732,7 +732,7 @@ void compis_state::machine_reset()
 
 static MACHINE_CONFIG_START( compis, compis_state )
 	// basic machine hardware
-	MCFG_CPU_ADD(I80186_TAG, I80186, XTAL_16MHz)
+	MCFG_CPU_ADD(I80186_TAG, I80186, XTAL_15_36MHz)
 	MCFG_CPU_PROGRAM_MAP(compis_mem)
 	MCFG_CPU_IO_MAP(compis_io)
 	MCFG_80186_IRQ_SLAVE_ACK(DEVREAD8(DEVICE_SELF, compis_state, compis_irq_callback))
@@ -740,17 +740,17 @@ static MACHINE_CONFIG_START( compis, compis_state )
 	MCFG_80186_TMROUT1_HANDLER(DEVWRITELINE(DEVICE_SELF, compis_state, tmr1_w))
 
 	// devices
-	MCFG_DEVICE_ADD(I80130_TAG, I80130, XTAL_16MHz/2)
+	MCFG_DEVICE_ADD(I80130_TAG, I80130, XTAL_15_36MHz/2)
 	MCFG_I80130_IRQ_CALLBACK(DEVWRITELINE(I80186_TAG, i80186_cpu_device, int0_w))
 	MCFG_I80130_SYSTICK_CALLBACK(DEVWRITELINE(I80130_TAG, i80130_device, ir3_w))
 	MCFG_I80130_DELAY_CALLBACK(DEVWRITELINE(I80130_TAG, i80130_device, ir7_w))
 	MCFG_I80130_BAUD_CALLBACK(WRITELINE(compis_state, tmr2_w))
 
 	MCFG_DEVICE_ADD(I8253_TAG, PIT8253, 0)
-	MCFG_PIT8253_CLK0(XTAL_16MHz/8)
+	MCFG_PIT8253_CLK0(XTAL_15_36MHz/8)
 	MCFG_PIT8253_OUT0_HANDLER(DEVWRITELINE(I8274_TAG, i8274_device, rxtxcb_w))
-	MCFG_PIT8253_CLK1(XTAL_16MHz/8)
-	MCFG_PIT8253_CLK2(XTAL_16MHz/8)
+	MCFG_PIT8253_CLK1(XTAL_15_36MHz/8)
+	MCFG_PIT8253_CLK2(XTAL_15_36MHz/8)
 	MCFG_PIT8253_OUT2_HANDLER(WRITELINE(compis_state, tmr5_w))
 
 	MCFG_DEVICE_ADD(I8255_TAG, I8255, 0)
@@ -766,7 +766,7 @@ static MACHINE_CONFIG_START( compis, compis_state )
 	MCFG_DEVICE_ADD(COMPIS_KEYBOARD_TAG, COMPIS_KEYBOARD, 0)
 	MCFG_COMPIS_KEYBOARD_OUT_TX_HANDLER(DEVWRITELINE(I8251A_TAG, i8251_device, write_rxd))
 
-	MCFG_I8274_ADD(I8274_TAG, XTAL_16MHz/4, 0, 0, 0, 0)
+	MCFG_I8274_ADD(I8274_TAG, XTAL_15_36MHz/4, 0, 0, 0, 0)
 	MCFG_Z80DART_OUT_TXDA_CB(DEVWRITELINE(RS232_A_TAG, rs232_port_device, write_txd))
 	MCFG_Z80DART_OUT_DTRA_CB(DEVWRITELINE(RS232_A_TAG, rs232_port_device, write_dtr))
 	MCFG_Z80DART_OUT_RTSA_CB(DEVWRITELINE(RS232_A_TAG, rs232_port_device, write_rts))
@@ -775,7 +775,7 @@ static MACHINE_CONFIG_START( compis, compis_state )
 	MCFG_Z80DART_OUT_RTSB_CB(DEVWRITELINE(RS232_B_TAG, rs232_port_device, write_rts))
 	MCFG_Z80DART_OUT_INT_CB(DEVWRITELINE(I80186_TAG, i80186_cpu_device, int3_w))
 
-	MCFG_DEVICE_ADD(MM58174A_TAG, MM58274C, 0)
+	MCFG_DEVICE_ADD(MM58174A_TAG, MM58274C, XTAL_32_768kHz)
 	MCFG_MM58274C_MODE24(0) // 12 hour
 	MCFG_MM58274C_DAY1(1)   // monday
 
@@ -799,7 +799,7 @@ static MACHINE_CONFIG_START( compis, compis_state )
 	MCFG_CENTRONICS_SELECT_HANDLER(WRITELINE(compis_state, write_centronics_select))
 	MCFG_CENTRONICS_OUTPUT_LATCH_ADD("cent_data_out", CENTRONICS_TAG)
 
-	MCFG_COMPIS_GRAPHICS_SLOT_ADD(GRAPHICS_TAG, XTAL_16MHz, compis_graphics_cards, "hrg")
+	MCFG_COMPIS_GRAPHICS_SLOT_ADD(GRAPHICS_TAG, XTAL_15_36MHz/2, compis_graphics_cards, "hrg")
 
 	MCFG_ISBX_SLOT_ADD(ISBX_0_TAG, 0, isbx_cards, "fdc")
 	MCFG_ISBX_SLOT_MINTR0_CALLBACK(DEVWRITELINE(I80130_TAG, i80130_device, ir1_w))
diff --git a/src/mame/machine/compiskb.cpp b/src/mame/machine/compiskb.cpp
index a7d0e0f895f..82da6141872 100644
--- a/src/mame/machine/compiskb.cpp
+++ b/src/mame/machine/compiskb.cpp
@@ -64,7 +64,7 @@ ADDRESS_MAP_END
 //-------------------------------------------------
 
 static MACHINE_CONFIG_FRAGMENT( compis_keyboard )
-	MCFG_CPU_ADD(I8748_TAG, I8748, XTAL_2MHz)
+	MCFG_CPU_ADD(I8748_TAG, I8748, 2016000) // XTAL_4_032MHz/2 ???
 	MCFG_CPU_IO_MAP(compis_keyboard_io)
 
 	// sound hardware