diff --git a/src/mame/drivers/vamphalf.cpp b/src/mame/drivers/vamphalf.cpp
index 9a7745fb5ae..b1b83d1ebbf 100644
--- a/src/mame/drivers/vamphalf.cpp
+++ b/src/mame/drivers/vamphalf.cpp
@@ -1117,7 +1117,7 @@ MACHINE_CONFIG_START(vamphalf_state::common)
 
 	/* video hardware */
 	MCFG_SCREEN_ADD("screen", RASTER)
-	MCFG_SCREEN_REFRESH_RATE(60)
+	MCFG_SCREEN_REFRESH_RATE(59)
 	MCFG_SCREEN_VBLANK_TIME(ATTOSECONDS_IN_USEC(0))
 	MCFG_SCREEN_SIZE(512, 256)
 	MCFG_SCREEN_VISIBLE_AREA(31, 350, 16, 251)
@@ -1950,6 +1950,10 @@ ROMs:
     VROM1           - MX 27C2000 2MBit DIP32 EPROM
     ROM1            - MX 27C4000 4MBit DIP32 EPROM
     ROM2            - MX 27C4000 4MBit DIP32 EPROM
+
+Measured Clocks:
+   H-Sync @ 15.625KHz
+   V-Sync @ 59.000Hz
 */
 
 ROM_START( coolmini )