thodg/cgminer

diff --git a/cgminer.c b/cgminer.c
index 663977f..c1be213 100644
--- a/cgminer.c
+++ b/cgminer.c
@@ -1238,7 +1238,7 @@ static struct opt_table opt_config_table[] = {
 		     "Set the hashfast overheat throttling temperature"),
 	OPT_WITH_ARG("--hfa-temp-target",
 		     set_int_0_to_200, opt_show_intval, &opt_hfa_target,
-		     "Set the hashfast target temperature"),
+		     "Set the hashfast target temperature (0 to disable)"),
 #endif
 #ifdef USE_KLONDIKE
 	OPT_WITH_ARG("--klondike-options",
diff --git a/driver-hashfast.c b/driver-hashfast.c
index 11c4a17..fa6fc01 100644
--- a/driver-hashfast.c
+++ b/driver-hashfast.c
@@ -980,6 +980,9 @@ static void hfa_temp_clock(struct cgpu_info *hashfast, struct hashfast_info *inf
 	time_t now_t = time(NULL);
 	int i;
 
+	if (!opt_hfa_target)
+		return;
+
 	for (i = 0; i < info->asic_count ; i++) {
 		struct hf_die_data *hdd = &info->die_data[i];