diff --git a/drivers/net/ethernet/intel/igb/igb_ptp.c b/drivers/net/ethernet/intel/igb/igb_ptp.c
index 29ced6b74d36..2b95dc9c7a6a 100644
--- a/drivers/net/ethernet/intel/igb/igb_ptp.c
+++ b/drivers/net/ethernet/intel/igb/igb_ptp.c
@@ -53,13 +53,15 @@
  *   2^40 * 10^-9 /  60  = 18.3 minutes.
  *
  * SYSTIM is converted to real time using a timecounter. As
- * timecounter_cyc2time() allows old timestamps, the timecounter
- * needs to be updated at least once per half of the SYSTIM interval.
- * Scheduling of delayed work is not very accurate, so we aim for 8
- * minutes to be sure the actual interval is shorter than 9.16 minutes.
+ * timecounter_cyc2time() allows old timestamps, the timecounter needs
+ * to be updated at least once per half of the SYSTIM interval.
+ * Scheduling of delayed work is not very accurate, and also the NIC
+ * clock can be adjusted to run up to 6% faster and the system clock
+ * up to 10% slower, so we aim for 6 minutes to be sure the actual
+ * interval in the NIC time is shorter than 9.16 minutes.
  */
 
-#define IGB_SYSTIM_OVERFLOW_PERIOD	(HZ * 60 * 8)
+#define IGB_SYSTIM_OVERFLOW_PERIOD	(HZ * 60 * 6)
 #define IGB_PTP_TX_TIMEOUT		(HZ * 15)
 #define INCPERIOD_82576			BIT(E1000_TIMINCA_16NS_SHIFT)
 #define INCVALUE_82576_MASK		GENMASK(E1000_TIMINCA_16NS_SHIFT - 1, 0)