diff --git a/biostools/analyzers.py b/biostools/analyzers.py
index 19f11a3..f827017 100644
--- a/biostools/analyzers.py
+++ b/biostools/analyzers.py
@@ -332,8 +332,12 @@ class AMIAnalyzer(Analyzer):
 		self._precolor_block_pattern = re.compile(b'''\(C\)(?:[0-9]{4}(?:AMI,404-263-8181|TGem-HCS,PSC,JGS)|( Access Methods Inc\.))''')
 		# "Date:-" might not have a space after it (Intel AMI)
 		self._precolor_date_pattern = re.compile(b'''(?:(?: Date:- ?|AMI- )[0-9]{2}/[0-9]{2}/[0-9]{2}|DDaattee(?:::|  )--(?:  )?([0-9])\\1([0-9])\\2//([0-9])\\3([0-9])\\4//([0-9])\\5([0-9])\\6)''')
-		# Decoded: "\xFE([^-]{4}-(?:[^-]{4}-)?[^-]{6})"
-		self._precolor_string_pattern = re.compile(b'''\\xFE([\\x00-\\x95\\x97-\\xFF]{4}\\x96(?:[\\x00-\\x95\\x97-\\xFF]{4}\\x96)?[\\x00-\\x95\\x97-\\xFF]{6})''')
+		# Variable gap between sync bytes (first bytes of the ROM) and the date.
+		self._precolor_core_date_pattern = re.compile(b'''\\xAA\\x55[\\x00-\\xFF]{1,16}([0-9]{2}/[0-9]{2}/[0-9]{2})''')
+		# Decoded: "\xFE([^-]{4}-(?:[0-9]{4}-)?[0-9]{6})"
+		self._precolor_string_pattern = re.compile(b'''\\xFE([\\x00-\\x95\\x97-\\xFF]{4}\\x96(?:[\\x7E\\x76\\x6E\\x66\\x5E\\x56\\x4E\\x46\\x3E\\x36]{4}\\x96)?[\\x7E\\x76\\x6E\\x66\\x5E\\x56\\x4E\\x46\\x3E\\x36]{6})''')
+		# Decoded: "\xFE([0-9]{4}-[0-9]{5}.)"
+		self._precolor_string_accm_pattern = re.compile(b'''\\xFE([\\x7E\\x76\\x6E\\x66\\x5E\\x56\\x4E\\x46\\x3E\\x36]{4}\\x96[\\x7E\\x76\\x6E\\x66\\x5E\\x56\\x4E\\x46\\x3E\\x36]{5}[\\x00-\\xFF])''')
 		self._precolor_signon_pattern = re.compile(b'''BIOS \(C\).*(?:AMI|American Megatrends Inc), for ([\\x0D\\x0A\\x20-\\x7E]+)''')
 		# Decoded: "\(C\)AMI, \(([^\)]{11})\)"
 		self._8088_string_pattern = re.compile(b'''\\xEC\\x5F\\x6C\\x60\\x5A\\x5C\\xEA\\xF0\\xEC([\\x00-\\x6B\\x6D-\\xFF]{11})\\x6C''')
@@ -408,7 +412,9 @@ class AMIAnalyzer(Analyzer):
 			return False
 		elif self._precolor_date_pattern.search(file_data):
 			# Check date, using a different pattern to differentiate core date from build date.
-			match = self._date_pattern.search(file_data)
+			match = self._precolor_core_date_pattern.search(file_data)
+			if not match:
+				match = self._date_pattern.search(file_data)
 			if match:
 				# Extract date as the version.
 				self.version = match.group(1).decode('cp437', 'ignore')
@@ -421,6 +427,8 @@ class AMIAnalyzer(Analyzer):
 
 					# Locate the encoded string.
 					match = self._precolor_string_pattern.search(file_data)
+					if not match:
+						match = self._precolor_string_accm_pattern.search(file_data)
 					if match:
 						# Extract string.
 						buf = []