diff --git a/src/mess/machine/amstrad.c b/src/mess/machine/amstrad.c
index cdc083d9719..a8014aa0b85 100644
--- a/src/mess/machine/amstrad.c
+++ b/src/mess/machine/amstrad.c
@@ -761,7 +761,7 @@ void amstrad_state::amstrad_plus_update_video()
 			m_gate_array.draw_p++;
 			cycles_passed--;
 			m_gate_array.line_ticks++;
-			if ( m_gate_array.line_ticks > m_gate_array.bitmap->width() )
+			if ( m_gate_array.line_ticks >= m_gate_array.bitmap->width() )
 			{
 				m_gate_array.draw_p = NULL;
 				cycles_passed = 0;