Works perfectly after several months of use (at a rate of several days a week) on my ancient ACER Aspire 5021. By cons although I suspected, and contrary to what is stated by the seller, it is not nine. CrystalDiskInfo with a little analysis before installation was given: Health status ..... Correct Number of ignitions 304x ..... Works since 16194 h ..... Reference Hitachi HTS 541680J9AT00