diff --git a/config-example.yaml b/config-example.yaml
index 485d87b..1dcda25 100644
--- a/config-example.yaml
+++ b/config-example.yaml
@@ -1,4 +1,5 @@
 loglevel: DEBUG
+interval: 1
 
 thermalzones:
   - name: GPU+SYSTEM
@@ -16,7 +17,7 @@ thermalzones:
     source: coretemp/temp1_input
     factor: 1000
     fan:
-      - it8686/pwm1
+      - it8686/pwm1: [100, 200]
     target: 50
     pid:
       p: 1
diff --git a/pyfan.py b/pyfan.py
index aadab04..399ea7d 100644
--- a/pyfan.py
+++ b/pyfan.py
@@ -36,14 +36,24 @@ class ThermalZone:
     def eval(self):
         if self.get_temp():
             diff = self.target - self.get_temp()
-            val = self.pid(diff)
+            val = int(self.pid(diff))
 
             try:
                 for target_fan in self.fans:
                     if type(target_fan) is dict:
-                        self.write_sysfs(list(target_fan.keys())[0], min(int(val), list(target_fan.values())[0]))
+                        fan = list(target_fan.keys())[0]
+                        fan_val = list(target_fan.values())[0]
+
+                        if type(fan_val) is list:
+                            if len(fan_val) < 2:
+                                logging.getLogger("pyfan").warning(
+                                    "[%s] max/min for %s was not set correctly (%s)" % (self.name, fan, fan_val))
+
+                            self.write_sysfs(fan, min(fan_val[1], max(val, fan_val[0])))
+                        else:
+                            self.write_sysfs(fan, min(val, fan_val))
                     else:
-                        self.write_sysfs(target_fan, int(val))
+                        self.write_sysfs(target_fan, val)
             except OSError as err:
                 logging.getLogger("pyfan").warning(
                     "[%s] Failed to set pwm, trying to reset it. (%s)" % (self.name, err.strerror))
@@ -74,8 +84,8 @@ class ThermalZone:
                 else:
                     self.set_pwm_mode(target_fan, value)
             except FileNotFoundError as err:
-                logging.getLogger("pyfan").warning("[%s] pwm not found. Not ready yet or wrong path? (%s)" % (self.name,
-                                                                                                              err.strerror))
+                logging.getLogger("pyfan").warning("[%s] pwm not found."
+                                                   " Not ready yet or wrong path? (%s)" % (self.name, err.strerror))
 
     def replace_alias(self, path):
         replaced = self.alias_replace.sub(lambda x: self.hwmap[x.group()], path)
@@ -111,6 +121,11 @@ class PyFan:
         self.hwmon_map = {}
         self.gen_hwmon_map()
 
+        if self.config["interval"]:
+            self.interval = self.config["interval"]
+        else:
+            self.interval = 1
+
         for zone in self.config["thermalzones"]:
             self.zones.append(ThermalZone(zone, self.hwmon_map))
 
@@ -147,6 +162,6 @@ if __name__ == "__main__":
         while True:
             try:
                 pyfan.eval()
-                sleep(1)
+                sleep(pyfan.interval)
             except KeyboardInterrupt:
                 sys.exit(0)