diff --git a/drivers/video/aty/radeon_monitor.c b/drivers/video/aty/radeon_monitor.c
index 7f9838dceab50f05421f7d3a53064e54db6bbd56..98c05bc0de44ac88c1e979d047c6f493b2d7ab0b 100644
--- a/drivers/video/aty/radeon_monitor.c
+++ b/drivers/video/aty/radeon_monitor.c
@@ -396,6 +396,10 @@ static int __devinit radeon_parse_monitor_layout(struct radeonfb_info *rinfo,
 				s1[i] = *s;
 			i++;
 		}
+
+		if (i > 4)
+			i = 4;
+
 	} while (*s++);
 	if (second)
 		s2[i] = 0;