diff --git a/CHANGES b/CHANGES
index 8231fa09..669723db 100644
--- a/CHANGES
+++ b/CHANGES
@@ -4,6 +4,7 @@ lm-sensors CHANGES file
 SVN-HEAD
   sensors-detect: Add nNidia nForce MCP78S SMBus detection
                   Display Super-I/O address even if LD is disabled
+                  Differentiate between PC8374L and WPCD377I
 
 3.1.0 "Happy Birthday Lina" (2009-02-28)
   libsensors: Add support for instantaneous power sensors
diff --git a/prog/detect/sensors-detect b/prog/detect/sensors-detect
index 2a32587d..a7b8294d 100755
--- a/prog/detect/sensors-detect
+++ b/prog/detect/sensors-detect
@@ -1163,6 +1163,9 @@ use vars qw(@i2c_adapter_names);
 #  devid: The device ID we have to match (base device)
 #  devid_mask (optional): Bitmask to apply before checking the device ID
 #  logdev: The logical device containing the sensors
+#  check (optional): A function to refine the detection. Will be passed
+#      the index and data ports as parameters. Must return 1 for a matching
+#      device, 0 otherwise.
 #  features (optional): Features supported by this device, amongst:
 #      * FEAT_IN
 #      * FEAT_FAN
@@ -1177,11 +1180,25 @@ use constant FEAT_SMBUS	=> (1 << 7);
 
 @superio_ids_natsemi = (
 	{
-		name => "Nat. Semi. PC8374L Super IO Sensors",
+		name => "Nat. Semi. PC8374L Super IO Sensors",	# Also Nuvoton WPCD374L
 		driver => "to-be-written",
 		devid => 0xf1,
+		check => sub {
+			outb($_[0], 0x27);
+			# Guess work; seen so far: 0x11
+			return (inb($_[1]) < 0x80);
+		},
 		logdev => 0x08,
 		features => FEAT_IN | FEAT_FAN | FEAT_TEMP,
+	}, {
+		name => "Nuvoton WPCD377I Super IO",	# Also WPCD376I
+		driver => "not-a-sensor",
+		devid => 0xf1,
+		check => sub {
+			outb($_[0], 0x27);
+			# Guess work; seen so far: 0x91 (twice)
+			return (inb($_[1]) >= 0x80);
+		},
 	}, {
 		name => "Nat. Semi. PC87351 Super IO Fan Sensors",
 		driver => "to-be-written",
@@ -3205,6 +3222,10 @@ sub probe_superio
 	my ($addrreg, $datareg, $chip) = @_;
 	my ($val, $addr);
 
+	if (exists $chip->{check}) {
+		return 0 unless $chip->{check}($addrreg, $datareg);
+	}
+
 	printf "\%-60s", "Found `$chip->{name}'";
 
 	# Does it have hardware monitoring capabilities?