diff --git usr.sbin/bhyve/pm.c usr.sbin/bhyve/pm.c
index da62aa2..111a379 100644
--- usr.sbin/bhyve/pm.c
+++ usr.sbin/bhyve/pm.c
@@ -191,7 +191,7 @@ pm1_enable_handler(struct vmctx *ctx, int vcpu, int in, int port, int bytes,
 		 * the global lock, but ACPI-CA whines profusely if it
 		 * can't set GBL_EN.
 		 */
-		pm1_enable = *eax & (PM1_PWRBTN_EN | PM1_GBL_EN);
+		pm1_enable = *eax & (PM1_RTC_EN | PM1_PWRBTN_EN | PM1_GBL_EN);
 		sci_update(ctx);
 	}
 	pthread_mutex_unlock(&pm_lock);