HP has installed a built-in chip to make sure that you replace the CB384A, CB385A, CB387A, CB386A image drums at certain intervals based on page yield. In most cases it is not necessary to replace the drum when you get the replace drum error message. If the drum you have was working correctly with good quality prints before the priinter displayed the ""Replace Drum Unit"" message then the drum can be reset with a new chip. The new chip which will reset the counter and you can print again.
Reset the imaging drum with a new chip so you can continue to use it. For the HP CP6015, CM6030 and CM6040 models.
