diff --git a/CHANGES b/CHANGES
index c361d40d..f42ea4fc 100644
--- a/CHANGES
+++ b/CHANGES
@@ -17,6 +17,7 @@ SVN HEAD
                   Add detection of LM95234
                   Add detection of TMP431/TMP432
                   Update Nuvoton chip information and NCT6106D chip detection
+                  Drop unreliable DS1621/DS1631 detection
 
 3.3.3 "Happy Birthday Sophie" (2012-11-06)
   documentation: Update fan-divisors, fan divisors are optional
diff --git a/prog/detect/sensors-detect b/prog/detect/sensors-detect
index e0ea2f2d..94dcf666 100755
--- a/prog/detect/sensors-detect
+++ b/prog/detect/sensors-detect
@@ -802,11 +802,6 @@ use vars qw(@i2c_adapter_names);
 		driver => "adm9240",
 		i2c_addrs => [0x2c..0x2f],
 		i2c_detect => sub { adm9240_detect(@_, 0); },
-	}, {
-		name => "Dallas Semiconductor DS1621/DS1631",
-		driver => "ds1621",
-		i2c_addrs => [0x48..0x4f],
-		i2c_detect => sub { ds1621_detect(@_); },
 	}, {
 		name => "Dallas Semiconductor DS1780",
 		driver => "adm9240",
@@ -4357,47 +4352,6 @@ sub lm92_detect
 	return ($chip == 0) ? 4 : 2;
 }
 
-# Registers used:
-#   0xAA: Temperature
-#   0xA1: High limit
-#   0xA2: Low limit
-#   0xA8: Counter
-#   0xA9: Slope
-#   0xAC: Configuration
-# Detection is weak. We check if bit 4 (NVB) is clear, because it is
-# unlikely to be set (would mean that EEPROM is currently being accessed).
-# We also check the value of the counter and slope registers, the datasheet
-# doesn't mention the possible values but the conversion formula together
-# with experimental evidence suggest possible sanity checks.
-# Not all devices enjoy SMBus read word transactions, so we do as much as
-# possible with read byte transactions first, and only use read word
-# transactions second.
-sub ds1621_detect
-{
-	my ($file, $addr) = @_;
-
-	my $conf = i2c_smbus_read_byte_data($file, 0xAC);
-	return if ($conf & 0x10);
-
-	my $temp = i2c_smbus_read_word_data($file, 0xAA);
-	return if $temp < 0 || ($temp & 0x0f00);
-	# On the DS1631, the following two checks are too strict in theory,
-	# but in practice I very much doubt that anyone will set temperature
-	# limits not a multiple of 0.5 degrees C.
-	my $high = i2c_smbus_read_word_data($file, 0xA1);
-	return if $high < 0 || ($high & 0x7f00);
-	my $low = i2c_smbus_read_word_data($file, 0xA2);
-	return if $low < 0 || ($low & 0x7f00);
-
-	return if ($temp == 0 && $high == 0 && $low == 0 && $conf == 0);
-
-	# Old versions of the DS1621 apparently don't have the counter and
-	# slope registers (or they return crap)
-	my $counter = i2c_smbus_read_byte_data($file, 0xA8);
-	my $slope = i2c_smbus_read_byte_data($file, 0xA9);
-	return ($slope == 0x10 && $counter <= $slope) ? 3 : 2;
-}
-
 # Chip to detect: 0 = LM80, 1 = LM96080
 # Registers used:
 #   0x00: Configuration register