Details are provided in the manual at this link: <ADMIN NOTE: Broken link has been removed from this post by Dell> . You require a heat sink. As I understand it these processors come in passive and active packages. The passive version has a heat sink. I recently fitted a second processor to my T7400 using a dell supplied package which included a heat sink with thermal grease already applied. I suspect you will need to identify suppliers on the Net who sell this processor and take their advice on how to obtain the required heat sink. Hope this helps.