Customer Information - Desktop/Tower A label with the serial number and support contact information is located on the right side of the computer. Another label with only the serial number is located on the rear of the computer. The label on the right side of the computer case provides the following: Model number Serial number Online Support Web address Tech Support phone number Tech Support hours of operation The label on the rear of the computer case is located below the fan vent. It provides the computer serial number and model number.